/* * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems) * * Copyright (C) 2014 Atmel Corporation * * Author: Ludovic Desroches * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program. If not, see . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "dmaengine.h" /* Global registers */ #define AT_XDMAC_GTYPE 0x00 /* Global Type Register */ #define AT_XDMAC_NB_CH(i) (((i) & 0x1F) + 1) /* Number of Channels Minus One */ #define AT_XDMAC_FIFO_SZ(i) (((i) >> 5) & 0x7FF) /* Number of Bytes */ #define AT_XDMAC_NB_REQ(i) ((((i) >> 16) & 0x3F) + 1) /* Number of Peripheral Requests Minus One */ #define AT_XDMAC_GCFG 0x04 /* Global Configuration Register */ #define AT_XDMAC_GWAC 0x08 /* Global Weighted Arbiter Configuration Register */ #define AT_XDMAC_GIE 0x0C /* Global Interrupt Enable Register */ #define AT_XDMAC_GID 0x10 /* Global Interrupt Disable Register */ #define AT_XDMAC_GIM 0x14 /* Global Interrupt Mask Register */ #define AT_XDMAC_GIS 0x18 /* Global Interrupt Status Register */ #define AT_XDMAC_GE 0x1C /* Global Channel Enable Register */ #define AT_XDMAC_GD 0x20 /* Global Channel Disable Register */ #define AT_XDMAC_GS 0x24 /* Global Channel Status Register */ #define AT_XDMAC_GRS 0x28 /* Global Channel Read Suspend Register */ #define AT_XDMAC_GWS 0x2C /* Global Write Suspend Register */ #define AT_XDMAC_GRWS 0x30 /* Global Channel Read Write Suspend Register */ #define AT_XDMAC_GRWR 0x34 /* Global Channel Read Write Resume Register */ #define AT_XDMAC_GSWR 0x38 /* Global Channel Software Request Register */ #define AT_XDMAC_GSWS 0x3C /* Global channel Software Request Status Register */ #define AT_XDMAC_GSWF 0x40 /* Global Channel Software Flush Request Register */ #define AT_XDMAC_VERSION 0xFFC /* XDMAC Version Register */ /* Channel relative registers offsets */ #define AT_XDMAC_CIE 0x00 /* Channel Interrupt Enable Register */ #define AT_XDMAC_CIE_BIE BIT(0) /* End of Block Interrupt Enable Bit */ #define AT_XDMAC_CIE_LIE BIT(1) /* End of Linked List Interrupt Enable Bit */ #define AT_XDMAC_CIE_DIE BIT(2) /* End of Disable Interrupt Enable Bit */ #define AT_XDMAC_CIE_FIE BIT(3) /* End of Flush Interrupt Enable Bit */ #define AT_XDMAC_CIE_RBEIE BIT(4) /* Read Bus Error Interrupt Enable Bit */ #define AT_XDMAC_CIE_WBEIE BIT(5) /* Write Bus Error Interrupt Enable Bit */ #define AT_XDMAC_CIE_ROIE BIT(6) /* Request Overflow Interrupt Enable Bit */ #define AT_XDMAC_CID 0x04 /* Channel Interrupt Disable Register */ #define AT_XDMAC_CID_BID BIT(0) /* End of Block Interrupt Disable Bit */ #define AT_XDMAC_CID_LID BIT(1) /* End of Linked List Interrupt Disable Bit */ #define AT_XDMAC_CID_DID BIT(2) /* End of Disable Interrupt Disable Bit */ #define AT_XDMAC_CID_FID BIT(3) /* End of Flush Interrupt Disable Bit */ #define AT_XDMAC_CID_RBEID BIT(4) /* Read Bus Error Interrupt Disable Bit */ #define AT_XDMAC_CID_WBEID BIT(5) /* Write Bus Error Interrupt Disable Bit */ #define AT_XDMAC_CID_ROID BIT(6) /* Request Overflow Interrupt Disable Bit */ #define AT_XDMAC_CIM 0x08 /* Channel Interrupt Mask Register */ #define AT_XDMAC_CIM_BIM BIT(0) /* End of Block Interrupt Mask Bit */ #define AT_XDMAC_CIM_LIM BIT(1) /* End of Linked List Interrupt Mask Bit */ #define AT_XDMAC_CIM_DIM BIT(2) /* End of Disable Interrupt Mask Bit */ #define AT_XDMAC_CIM_FIM BIT(3) /* End of Flush Interrupt Mask Bit */ #define AT_XDMAC_CIM_RBEIM BIT(4) /* Read Bus Error Interrupt Mask Bit */ #define AT_XDMAC_CIM_WBEIM BIT(5) /* Write Bus Error Interrupt Mask Bit */ #define AT_XDMAC_CIM_ROIM BIT(6) /* Request Overflow Interrupt Mask Bit */ #define AT_XDMAC_CIS 0x0C /* Channel Interrupt Status Register */ #define AT_XDMAC_CIS_BIS BIT(0) /* End of Block Interrupt Status Bit */ #define AT_XDMAC_CIS_LIS BIT(1) /* End of Linked List Interrupt Status Bit */ #define AT_XDMAC_CIS_DIS BIT(2) /* End of Disable Interrupt Status Bit */ #define AT_XDMAC_CIS_FIS BIT(3) /* End of Flush Interrupt Status Bit */ #define AT_XDMAC_CIS_RBEIS BIT(4) /* Read Bus Error Interrupt Status Bit */ #define AT_XDMAC_CIS_WBEIS BIT(5) /* Write Bus Error Interrupt Status Bit */ #define AT_XDMAC_CIS_ROIS BIT(6) /* Request Overflow Interrupt Status Bit */ #define AT_XDMAC_CSA 0x10 /* Channel Source Address Register */ #define AT_XDMAC_CDA 0x14 /* Channel Destination Address Register */ #define AT_XDMAC_CNDA 0x18 /* Channel Next Descriptor Address Register */ #define AT_XDMAC_CNDA_NDAIF(i) ((i) & 0x1) /* Channel x Next Descriptor Interface */ #define AT_XDMAC_CNDA_NDA(i) ((i) & 0xfffffffc) /* Channel x Next Descriptor Address */ #define AT_XDMAC_CNDC 0x1C /* Channel Next Descriptor Control Register */ #define AT_XDMAC_CNDC_NDE (0x1 << 0) /* Channel x Next Descriptor Enable */ #define AT_XDMAC_CNDC_NDSUP (0x1 << 1) /* Channel x Next Descriptor Source Update */ #define AT_XDMAC_CNDC_NDDUP (0x1 << 2) /* Channel x Next Descriptor Destination Update */ #define AT_XDMAC_CNDC_NDVIEW_MASK GENMASK(28, 27) #define AT_XDMAC_CNDC_NDVIEW_NDV0 (0x0 << 3) /* Channel x Next Descriptor View 0 */ #define AT_XDMAC_CNDC_NDVIEW_NDV1 (0x1 << 3) /* Channel x Next Descriptor View 1 */ #define AT_XDMAC_CNDC_NDVIEW_NDV2 (0x2 << 3) /* Channel x Next Descriptor View 2 */ #define AT_XDMAC_CNDC_NDVIEW_NDV3 (0x3 << 3) /* Channel x Next Descriptor View 3 */ #define AT_XDMAC_CUBC 0x20 /* Channel Microblock Control Register */ #define AT_XDMAC_CBC 0x24 /* Channel Block Control Register */ #define AT_XDMAC_CC 0x28 /* Channel Configuration Register */ #define AT_XDMAC_CC_TYPE (0x1 << 0) /* Channel Transfer Type */ #define AT_XDMAC_CC_TYPE_MEM_TRAN (0x0 << 0) /* Memory to Memory Transfer */ #define AT_XDMAC_CC_TYPE_PER_TRAN (0x1 << 0) /* Peripheral to Memory or Memory to Peripheral Transfer */ #define AT_XDMAC_CC_MBSIZE_MASK (0x3 << 1) #define AT_XDMAC_CC_MBSIZE_SINGLE (0x0 << 1) #define AT_XDMAC_CC_MBSIZE_FOUR (0x1 << 1) #define AT_XDMAC_CC_MBSIZE_EIGHT (0x2 << 1) #define AT_XDMAC_CC_MBSIZE_SIXTEEN (0x3 << 1) #define AT_XDMAC_CC_DSYNC (0x1 << 4) /* Channel Synchronization */ #define AT_XDMAC_CC_DSYNC_PER2MEM (0x0 << 4) #define AT_XDMAC_CC_DSYNC_MEM2PER (0x1 << 4) #define AT_XDMAC_CC_PROT (0x1 << 5) /* Channel Protection */ #define AT_XDMAC_CC_PROT_SEC (0x0 << 5) #define AT_XDMAC_CC_PROT_UNSEC (0x1 << 5) #define AT_XDMAC_CC_SWREQ (0x1 << 6) /* Channel Software Request Trigger */ #define AT_XDMAC_CC_SWREQ_HWR_CONNECTED (0x0 << 6) #define AT_XDMAC_CC_SWREQ_SWR_CONNECTED (0x1 << 6) #define AT_XDMAC_CC_MEMSET (0x1 << 7) /* Channel Fill Block of memory */ #define AT_XDMAC_CC_MEMSET_NORMAL_MODE (0x0 << 7) #define AT_XDMAC_CC_MEMSET_HW_MODE (0x1 << 7) #define AT_XDMAC_CC_CSIZE(i) ((0x7 & (i)) << 8) /* Channel Chunk Size */ #define AT_XDMAC_CC_DWIDTH_OFFSET 11 #define AT_XDMAC_CC_DWIDTH_MASK (0x3 << AT_XDMAC_CC_DWIDTH_OFFSET) #define AT_XDMAC_CC_DWIDTH(i) ((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET) /* Channel Data Width */ #define AT_XDMAC_CC_DWIDTH_BYTE 0x0 #define AT_XDMAC_CC_DWIDTH_HALFWORD 0x1 #define AT_XDMAC_CC_DWIDTH_WORD 0x2 #define AT_XDMAC_CC_DWIDTH_DWORD 0x3 #define AT_XDMAC_CC_SIF(i) ((0x1 & (i)) << 13) /* Channel Source Interface Identifier */ #define AT_XDMAC_CC_DIF(i) ((0x1 & (i)) << 14) /* Channel Destination Interface Identifier */ #define AT_XDMAC_CC_SAM_MASK (0x3 << 16) /* Channel Source Addressing Mode */ #define AT_XDMAC_CC_SAM_FIXED_AM (0x0 << 16) #define AT_XDMAC_CC_SAM_INCREMENTED_AM (0x1 << 16) #define AT_XDMAC_CC_SAM_UBS_AM (0x2 << 16) #define AT_XDMAC_CC_SAM_UBS_DS_AM (0x3 << 16) #define AT_XDMAC_CC_DAM_MASK (0x3 << 18) /* Channel Source Addressing Mode */ #define AT_XDMAC_CC_DAM_FIXED_AM (0x0 << 18) #define AT_XDMAC_CC_DAM_INCREMENTED_AM (0x1 << 18) #define AT_XDMAC_CC_DAM_UBS_AM (0x2 << 18) #define AT_XDMAC_CC_DAM_UBS_DS_AM (0x3 << 18) #define AT_XDMAC_CC_INITD (0x1 << 21) /* Channel Initialization Terminated (read only) */ #define AT_XDMAC_CC_INITD_TERMINATED (0x0 << 21) #define AT_XDMAC_CC_INITD_IN_PROGRESS (0x1 << 21) #define AT_XDMAC_CC_RDIP (0x1 << 22) /* Read in Progress (read only) */ #define AT_XDMAC_CC_RDIP_DONE (0x0 << 22) #define AT_XDMAC_CC_RDIP_IN_PROGRESS (0x1 << 22) #define AT_XDMAC_CC_WRIP (0x1 << 23) /* Write in Progress (read only) */ #define AT_XDMAC_CC_WRIP_DONE (0x0 << 23) #define AT_XDMAC_CC_WRIP_IN_PROGRESS (0x1 << 23) #define AT_XDMAC_CC_PERID(i) ((0x7f & (i)) << 24) /* Channel Peripheral Identifier */ #define AT_XDMAC_CDS_MSP 0x2C /* Channel Data Stride Memory Set Pattern */ #define AT_XDMAC_CSUS 0x30 /* Channel Source Microblock Stride */ #define AT_XDMAC_CDUS 0x34 /* Channel Destination Microblock Stride */ #define AT_XDMAC_CHAN_REG_BASE 0x50 /* Channel registers base address */ /* Microblock control members */ #define AT_XDMAC_MBR_UBC_UBLEN_MAX 0xFFFFFFUL /* Maximum Microblock Length */ #define AT_XDMAC_MBR_UBC_NDE (0x1 << 24) /* Next Descriptor Enable */ #define AT_XDMAC_MBR_UBC_NSEN (0x1 << 25) /* Next Descriptor Source Update */ #define AT_XDMAC_MBR_UBC_NDEN (0x1 << 26) /* Next Descriptor Destination Update */ #define AT_XDMAC_MBR_UBC_NDV0 (0x0 << 27) /* Next Descriptor View 0 */ #define AT_XDMAC_MBR_UBC_NDV1 (0x1 << 27) /* Next Descriptor View 1 */ #define AT_XDMAC_MBR_UBC_NDV2 (0x2 << 27) /* Next Descriptor View 2 */ #define AT_XDMAC_MBR_UBC_NDV3 (0x3 << 27) /* Next Descriptor View 3 */ #define AT_XDMAC_MAX_CHAN 0x20 #define AT_XDMAC_MAX_CSIZE 16 /* 16 data */ #define AT_XDMAC_MAX_DWIDTH 8 /* 64 bits */ #define AT_XDMAC_RESIDUE_MAX_RETRIES 5 #define AT_XDMAC_DMA_BUSWIDTHS\ (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\ BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\ BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)) enum atc_status { AT_XDMAC_CHAN_IS_CYCLIC = 0, AT_XDMAC_CHAN_IS_PAUSED, }; /* ----- Channels ----- */ struct at_xdmac_chan { struct dma_chan chan; void __iomem *ch_regs; u32 mask; /* Channel Mask */ u32 cfg; /* Channel Configuration Register */ u8 perid; /* Peripheral ID */ u8 perif; /* Peripheral Interface */ u8 memif; /* Memory Interface */ u32 save_cc; u32 save_cim; u32 save_cnda; u32 save_cndc; u32 irq_status; unsigned long status; struct tasklet_struct tasklet; struct dma_slave_config sconfig; spinlock_t lock; struct list_head xfers_list; struct list_head free_descs_list; }; /* ----- Controller ----- */ struct at_xdmac { struct dma_device dma; void __iomem *regs; int irq; struct clk *clk; u32 save_gim; u32 save_gs; struct dma_pool *at_xdmac_desc_pool; struct at_xdmac_chan chan[0]; }; /* ----- Descriptors ----- */ /* Linked List Descriptor */ struct at_xdmac_lld { u32 mbr_nda; /* Next Descriptor Member */ u32 mbr_ubc; /* Microblock Control Member */ u32 mbr_sa; /* Source Address Member */ u32 mbr_da; /* Destination Address Member */ u32 mbr_cfg; /* Configuration Register */ u32 mbr_bc; /* Block Control Register */ u32 mbr_ds; /* Data Stride Register */ u32 mbr_sus; /* Source Microblock Stride Register */ u32 mbr_dus; /* Destination Microblock Stride Register */ }; /* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */ struct at_xdmac_desc { struct at_xdmac_lld lld; enum dma_transfer_direction direction; struct dma_async_tx_descriptor tx_dma_desc; struct list_head desc_node; /* Following members are only used by the first descriptor */ bool active_xfer; unsigned int xfer_size; struct list_head descs_list; struct list_head xfer_node; } __aligned(sizeof(u64)); static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb) { return atxdmac->regs + (AT_XDMAC_CHAN_REG_BASE + chan_nb * 0x40); } #define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg)) #define at_xdmac_write(atxdmac, reg, value) \ writel_relaxed((value), (atxdmac)->regs + (reg)) #define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg)) #define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg)) static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan) { return container_of(dchan, struct at_xdmac_chan, chan); } static struct device *chan2dev(struct dma_chan *chan) { return &chan->dev->device; } static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev) { return container_of(ddev, struct at_xdmac, dma); } static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd) { return container_of(txd, struct at_xdmac_desc, tx_dma_desc); } static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan) { return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status); } static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan) { return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status); } static inline int at_xdmac_csize(u32 maxburst) { int csize; csize = ffs(maxburst) - 1; if (csize > 4) csize = -EINVAL; return csize; }; static inline u8 at_xdmac_get_dwidth(u32 cfg) { return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET; }; static unsigned int init_nr_desc_per_channel = 64; module_param(init_nr_desc_per_channel, uint, 0644); MODULE_PARM_DESC(init_nr_desc_per_channel, "initial descriptors per channel (default: 64)"); static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan) { return at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask; } static void at_xdmac_off(struct at_xdmac *atxdmac) { at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L); /* Wait that all chans are disabled. */ while (at_xdmac_read(atxdmac, AT_XDMAC_GS)) cpu_relax(); at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L); } /* Call with lock hold. */ static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan, struct at_xdmac_desc *first) { struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device); u32 reg; dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first); /* Set transfer as active to not try to start it again. */ first->active_xfer = true; /* Tell xdmac where to get the first descriptor. */ reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys) | AT_XDMAC_CNDA_NDAIF(atchan->memif); at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg); /* * When doing non cyclic transfer we need to use the next * descriptor view 2 since some fields of the configuration register * depend on transfer size and src/dest addresses. */ if (at_xdmac_chan_is_cyclic(atchan)) reg = AT_XDMAC_CNDC_NDVIEW_NDV1; else if ((first->lld.mbr_ubc & AT_XDMAC_CNDC_NDVIEW_MASK) == AT_XDMAC_MBR_UBC_NDV3) reg = AT_XDMAC_CNDC_NDVIEW_NDV3; else reg = AT_XDMAC_CNDC_NDVIEW_NDV2; /* * Even if the register will be updated from the configuration in the * descriptor when using view 2 or higher, the PROT bit won't be set * properly. This bit can be modified only by using the channel * configuration register. */ at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg); reg |= AT_XDMAC_CNDC_NDDUP | AT_XDMAC_CNDC_NDSUP | AT_XDMAC_CNDC_NDE; at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg); dev_vdbg(chan2dev(&atchan->chan), "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n", __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC), at_xdmac_chan_read(atchan, AT_XDMAC_CNDA), at_xdmac_chan_read(atchan, AT_XDMAC_CNDC), at_xdmac_chan_read(atchan, AT_XDMAC_CSA), at_xdmac_chan_read(atchan, AT_XDMAC_CDA), at_xdmac_chan_read(atchan, AT_XDMAC_CUBC)); at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff); reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE | AT_XDMAC_CIE_ROIE; /* * There is no end of list when doing cyclic dma, we need to get * an interrupt after each periods. */ if (at_xdmac_chan_is_cyclic(atchan)) at_xdmac_chan_write(atchan, AT_XDMAC_CIE, reg | AT_XDMAC_CIE_BIE); else at_xdmac_chan_write(atchan, AT_XDMAC_CIE, reg | AT_XDMAC_CIE_LIE); at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask); dev_vdbg(chan2dev(&atchan->chan), "%s: enable channel (0x%08x)\n", __func__, atchan->mask); wmb(); at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask); dev_vdbg(chan2dev(&atchan->chan), "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n", __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC), at_xdmac_chan_read(atchan, AT_XDMAC_CNDA), at_xdmac_chan_read(atchan, AT_XDMAC_CNDC), at_xdmac_chan_read(atchan, AT_XDMAC_CSA), at_xdmac_chan_read(atchan, AT_XDMAC_CDA), at_xdmac_chan_read(atchan, AT_XDMAC_CUBC)); } static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx) { struct at_xdmac_desc *desc = txd_to_at_desc(tx); struct at_xdmac_chan *atchan = to_at_xdmac_chan(tx->chan); dma_cookie_t cookie; unsigned long irqflags; spin_lock_irqsave(&atchan->lock, irqflags); cookie = dma_cookie_assign(tx); list_add_tail(&desc->xfer_node, &atchan->xfers_list); spin_unlock_irqrestore(&atchan->lock, irqflags); dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n", __func__, atchan, desc); return cookie; } static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan, gfp_t gfp_flags) { struct at_xdmac_desc *desc; struct at_xdmac *atxdmac = to_at_xdmac(chan->device); dma_addr_t phys; desc = dma_pool_alloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys); if (desc) { memset(desc, 0, sizeof(*desc)); INIT_LIST_HEAD(&desc->descs_list); dma_async_tx_descriptor_init(&desc->tx_dma_desc, chan); desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit; desc->tx_dma_desc.phys = phys; } return desc; } static void at_xdmac_init_used_desc(struct at_xdmac_desc *desc) { memset(&desc->lld, 0, sizeof(desc->lld)); INIT_LIST_HEAD(&desc->descs_list); desc->direction = DMA_TRANS_NONE; desc->xfer_size = 0; desc->active_xfer = false; } /* Call must be protected by lock. */ static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan) { struct at_xdmac_desc *desc; if (list_empty(&atchan->free_descs_list)) { desc = at_xdmac_alloc_desc(&atchan->chan, GFP_NOWAIT); } else { desc = list_first_entry(&atchan->free_descs_list, struct at_xdmac_desc, desc_node); list_del(&desc->desc_node); at_xdmac_init_used_desc(desc); } return desc; } static void at_xdmac_queue_desc(struct dma_chan *chan, struct at_xdmac_desc *prev, struct at_xdmac_desc *desc) { if (!prev || !desc) return; prev->lld.mbr_nda = desc->tx_dma_desc.phys; prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE; dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=%pad\n", __func__, prev, &prev->lld.mbr_nda); } static inline void at_xdmac_increment_block_count(struct dma_chan *chan, struct at_xdmac_desc *desc) { if (!desc) return; desc->lld.mbr_bc++; dev_dbg(chan2dev(chan), "%s: incrementing the block count of the desc 0x%p\n", __func__, desc); } static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec, struct of_dma *of_dma) { struct at_xdmac *atxdmac = of_dma->of_dma_data; struct at_xdmac_chan *atchan; struct dma_chan *chan; struct device *dev = atxdmac->dma.dev; if (dma_spec->args_count != 1) { dev_err(dev, "dma phandler args: bad number of args\n"); return NULL; } chan = dma_get_any_slave_channel(&atxdmac->dma); if (!chan) { dev_err(dev, "can't get a dma channel\n"); return NULL; } atchan = to_at_xdmac_chan(chan); atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]); atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]); atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]); dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n", atchan->memif, atchan->perif, atchan->perid); return chan; } static int at_xdmac_compute_chan_conf(struct dma_chan *chan, enum dma_transfer_direction direction) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); int csize, dwidth; if (direction == DMA_DEV_TO_MEM) { atchan->cfg = AT91_XDMAC_DT_PERID(atchan->perid) | AT_XDMAC_CC_DAM_INCREMENTED_AM | AT_XDMAC_CC_SAM_FIXED_AM | AT_XDMAC_CC_DIF(atchan->memif) | AT_XDMAC_CC_SIF(atchan->perif) | AT_XDMAC_CC_SWREQ_HWR_CONNECTED | AT_XDMAC_CC_DSYNC_PER2MEM | AT_XDMAC_CC_MBSIZE_SIXTEEN | AT_XDMAC_CC_TYPE_PER_TRAN; csize = ffs(atchan->sconfig.src_maxburst) - 1; if (csize < 0) { dev_err(chan2dev(chan), "invalid src maxburst value\n"); return -EINVAL; } atchan->cfg |= AT_XDMAC_CC_CSIZE(csize); dwidth = ffs(atchan->sconfig.src_addr_width) - 1; if (dwidth < 0) { dev_err(chan2dev(chan), "invalid src addr width value\n"); return -EINVAL; } atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth); } else if (direction == DMA_MEM_TO_DEV) { atchan->cfg = AT91_XDMAC_DT_PERID(atchan->perid) | AT_XDMAC_CC_DAM_FIXED_AM | AT_XDMAC_CC_SAM_INCREMENTED_AM | AT_XDMAC_CC_DIF(atchan->perif) | AT_XDMAC_CC_SIF(atchan->memif) | AT_XDMAC_CC_SWREQ_HWR_CONNECTED | AT_XDMAC_CC_DSYNC_MEM2PER | AT_XDMAC_CC_MBSIZE_SIXTEEN | AT_XDMAC_CC_TYPE_PER_TRAN; csize = ffs(atchan->sconfig.dst_maxburst) - 1; if (csize < 0) { dev_err(chan2dev(chan), "invalid src maxburst value\n"); return -EINVAL; } atchan->cfg |= AT_XDMAC_CC_CSIZE(csize); dwidth = ffs(atchan->sconfig.dst_addr_width) - 1; if (dwidth < 0) { dev_err(chan2dev(chan), "invalid dst addr width value\n"); return -EINVAL; } atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth); } dev_dbg(chan2dev(chan), "%s: cfg=0x%08x\n", __func__, atchan->cfg); return 0; } /* * Only check that maxburst and addr width values are supported by the * the controller but not that the configuration is good to perform the * transfer since we don't know the direction at this stage. */ static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig) { if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE) || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE)) return -EINVAL; if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH) || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH)) return -EINVAL; return 0; } static int at_xdmac_set_slave_config(struct dma_chan *chan, struct dma_slave_config *sconfig) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); if (at_xdmac_check_slave_config(sconfig)) { dev_err(chan2dev(chan), "invalid slave configuration\n"); return -EINVAL; } memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig)); return 0; } static struct dma_async_tx_descriptor * at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction direction, unsigned long flags, void *context) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac_desc *first = NULL, *prev = NULL; struct scatterlist *sg; int i; unsigned int xfer_size = 0; unsigned long irqflags; struct dma_async_tx_descriptor *ret = NULL; if (!sgl) return NULL; if (!is_slave_direction(direction)) { dev_err(chan2dev(chan), "invalid DMA direction\n"); return NULL; } dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n", __func__, sg_len, direction == DMA_MEM_TO_DEV ? "to device" : "from device", flags); /* Protect dma_sconfig field that can be modified by set_slave_conf. */ spin_lock_irqsave(&atchan->lock, irqflags); if (at_xdmac_compute_chan_conf(chan, direction)) goto spin_unlock; /* Prepare descriptors. */ for_each_sg(sgl, sg, sg_len, i) { struct at_xdmac_desc *desc = NULL; u32 len, mem, dwidth, fixed_dwidth; len = sg_dma_len(sg); mem = sg_dma_address(sg); if (unlikely(!len)) { dev_err(chan2dev(chan), "sg data length is zero\n"); goto spin_unlock; } dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n", __func__, i, len, mem); desc = at_xdmac_get_desc(atchan); if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) list_splice_init(&first->descs_list, &atchan->free_descs_list); goto spin_unlock; } /* Linked list descriptor setup. */ if (direction == DMA_DEV_TO_MEM) { desc->lld.mbr_sa = atchan->sconfig.src_addr; desc->lld.mbr_da = mem; } else { desc->lld.mbr_sa = mem; desc->lld.mbr_da = atchan->sconfig.dst_addr; } dwidth = at_xdmac_get_dwidth(atchan->cfg); fixed_dwidth = IS_ALIGNED(len, 1 << dwidth) ? dwidth : AT_XDMAC_CC_DWIDTH_BYTE; desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2 /* next descriptor view */ | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */ | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */ | (len >> fixed_dwidth); /* microblock length */ desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) | AT_XDMAC_CC_DWIDTH(fixed_dwidth); dev_dbg(chan2dev(chan), "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n", __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc); /* Chain lld. */ if (prev) at_xdmac_queue_desc(chan, prev, desc); prev = desc; if (!first) first = desc; dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n", __func__, desc, first); list_add_tail(&desc->desc_node, &first->descs_list); xfer_size += len; } first->tx_dma_desc.flags = flags; first->xfer_size = xfer_size; first->direction = direction; ret = &first->tx_dma_desc; spin_unlock: spin_unlock_irqrestore(&atchan->lock, irqflags); return ret; } static struct dma_async_tx_descriptor * at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, size_t period_len, enum dma_transfer_direction direction, unsigned long flags) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac_desc *first = NULL, *prev = NULL; unsigned int periods = buf_len / period_len; int i; unsigned long irqflags; dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n", __func__, &buf_addr, buf_len, period_len, direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags); if (!is_slave_direction(direction)) { dev_err(chan2dev(chan), "invalid DMA direction\n"); return NULL; } if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) { dev_err(chan2dev(chan), "channel currently used\n"); return NULL; } if (at_xdmac_compute_chan_conf(chan, direction)) return NULL; for (i = 0; i < periods; i++) { struct at_xdmac_desc *desc = NULL; spin_lock_irqsave(&atchan->lock, irqflags); desc = at_xdmac_get_desc(atchan); if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) list_splice_init(&first->descs_list, &atchan->free_descs_list); spin_unlock_irqrestore(&atchan->lock, irqflags); return NULL; } spin_unlock_irqrestore(&atchan->lock, irqflags); dev_dbg(chan2dev(chan), "%s: desc=0x%p, tx_dma_desc.phys=%pad\n", __func__, desc, &desc->tx_dma_desc.phys); if (direction == DMA_DEV_TO_MEM) { desc->lld.mbr_sa = atchan->sconfig.src_addr; desc->lld.mbr_da = buf_addr + i * period_len; } else { desc->lld.mbr_sa = buf_addr + i * period_len; desc->lld.mbr_da = atchan->sconfig.dst_addr; } desc->lld.mbr_cfg = atchan->cfg; desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1 | AT_XDMAC_MBR_UBC_NDEN | AT_XDMAC_MBR_UBC_NSEN | period_len >> at_xdmac_get_dwidth(desc->lld.mbr_cfg); dev_dbg(chan2dev(chan), "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n", __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc); /* Chain lld. */ if (prev) at_xdmac_queue_desc(chan, prev, desc); prev = desc; if (!first) first = desc; dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n", __func__, desc, first); list_add_tail(&desc->desc_node, &first->descs_list); } at_xdmac_queue_desc(chan, prev, first); first->tx_dma_desc.flags = flags; first->xfer_size = buf_len; first->direction = direction; return &first->tx_dma_desc; } static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr) { u32 width; /* * Check address alignment to select the greater data width we * can use. * * Some XDMAC implementations don't provide dword transfer, in * this case selecting dword has the same behavior as * selecting word transfers. */ if (!(addr & 7)) { width = AT_XDMAC_CC_DWIDTH_DWORD; dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__); } else if (!(addr & 3)) { width = AT_XDMAC_CC_DWIDTH_WORD; dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__); } else if (!(addr & 1)) { width = AT_XDMAC_CC_DWIDTH_HALFWORD; dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__); } else { width = AT_XDMAC_CC_DWIDTH_BYTE; dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__); } return width; } static struct at_xdmac_desc * at_xdmac_interleaved_queue_desc(struct dma_chan *chan, struct at_xdmac_chan *atchan, struct at_xdmac_desc *prev, dma_addr_t src, dma_addr_t dst, struct dma_interleaved_template *xt, struct data_chunk *chunk) { struct at_xdmac_desc *desc; u32 dwidth; unsigned long flags; size_t ublen; /* * WARNING: The channel configuration is set here since there is no * dmaengine_slave_config call in this case. Moreover we don't know the * direction, it involves we can't dynamically set the source and dest * interface so we have to use the same one. Only interface 0 allows EBI * access. Hopefully we can access DDR through both ports (at least on * SAMA5D4x), so we can use the same interface for source and dest, * that solves the fact we don't know the direction. * ERRATA: Even if useless for memory transfers, the PERID has to not * match the one of another channel. If not, it could lead to spurious * flag status. */ u32 chan_cc = AT_XDMAC_CC_PERID(0x3f) | AT_XDMAC_CC_DIF(0) | AT_XDMAC_CC_SIF(0) | AT_XDMAC_CC_MBSIZE_SIXTEEN | AT_XDMAC_CC_TYPE_MEM_TRAN; dwidth = at_xdmac_align_width(chan, src | dst | chunk->size); if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) { dev_dbg(chan2dev(chan), "%s: chunk too big (%d, max size %lu)...\n", __func__, chunk->size, AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth); return NULL; } if (prev) dev_dbg(chan2dev(chan), "Adding items at the end of desc 0x%p\n", prev); if (xt->src_inc) { if (xt->src_sgl) chan_cc |= AT_XDMAC_CC_SAM_UBS_AM; else chan_cc |= AT_XDMAC_CC_SAM_INCREMENTED_AM; } if (xt->dst_inc) { if (xt->dst_sgl) chan_cc |= AT_XDMAC_CC_DAM_UBS_AM; else chan_cc |= AT_XDMAC_CC_DAM_INCREMENTED_AM; } spin_lock_irqsave(&atchan->lock, flags); desc = at_xdmac_get_desc(atchan); spin_unlock_irqrestore(&atchan->lock, flags); if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); return NULL; } chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth); ublen = chunk->size >> dwidth; desc->lld.mbr_sa = src; desc->lld.mbr_da = dst; desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk); desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk); desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3 | AT_XDMAC_MBR_UBC_NDEN | AT_XDMAC_MBR_UBC_NSEN | ublen; desc->lld.mbr_cfg = chan_cc; dev_dbg(chan2dev(chan), "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n", __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg); /* Chain lld. */ if (prev) at_xdmac_queue_desc(chan, prev, desc); return desc; } static struct dma_async_tx_descriptor * at_xdmac_prep_interleaved(struct dma_chan *chan, struct dma_interleaved_template *xt, unsigned long flags) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac_desc *prev = NULL, *first = NULL; dma_addr_t dst_addr, src_addr; size_t src_skip = 0, dst_skip = 0, len = 0; struct data_chunk *chunk; int i; if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM)) return NULL; /* * TODO: Handle the case where we have to repeat a chain of * descriptors... */ if ((xt->numf > 1) && (xt->frame_size > 1)) return NULL; dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%d, frame_size=%d, flags=0x%lx\n", __func__, &xt->src_start, &xt->dst_start, xt->numf, xt->frame_size, flags); src_addr = xt->src_start; dst_addr = xt->dst_start; if (xt->numf > 1) { first = at_xdmac_interleaved_queue_desc(chan, atchan, NULL, src_addr, dst_addr, xt, xt->sgl); /* Length of the block is (BLEN+1) microblocks. */ for (i = 0; i < xt->numf - 1; i++) at_xdmac_increment_block_count(chan, first); dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n", __func__, first, first); list_add_tail(&first->desc_node, &first->descs_list); } else { for (i = 0; i < xt->frame_size; i++) { size_t src_icg = 0, dst_icg = 0; struct at_xdmac_desc *desc; chunk = xt->sgl + i; dst_icg = dmaengine_get_dst_icg(xt, chunk); src_icg = dmaengine_get_src_icg(xt, chunk); src_skip = chunk->size + src_icg; dst_skip = chunk->size + dst_icg; dev_dbg(chan2dev(chan), "%s: chunk size=%d, src icg=%d, dst icg=%d\n", __func__, chunk->size, src_icg, dst_icg); desc = at_xdmac_interleaved_queue_desc(chan, atchan, prev, src_addr, dst_addr, xt, chunk); if (!desc) { list_splice_init(&first->descs_list, &atchan->free_descs_list); return NULL; } if (!first) first = desc; dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n", __func__, desc, first); list_add_tail(&desc->desc_node, &first->descs_list); if (xt->src_sgl) src_addr += src_skip; if (xt->dst_sgl) dst_addr += dst_skip; len += chunk->size; prev = desc; } } first->tx_dma_desc.cookie = -EBUSY; first->tx_dma_desc.flags = flags; first->xfer_size = len; return &first->tx_dma_desc; } static struct dma_async_tx_descriptor * at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac_desc *first = NULL, *prev = NULL; size_t remaining_size = len, xfer_size = 0, ublen; dma_addr_t src_addr = src, dst_addr = dest; u32 dwidth; /* * WARNING: We don't know the direction, it involves we can't * dynamically set the source and dest interface so we have to use the * same one. Only interface 0 allows EBI access. Hopefully we can * access DDR through both ports (at least on SAMA5D4x), so we can use * the same interface for source and dest, that solves the fact we * don't know the direction. * ERRATA: Even if useless for memory transfers, the PERID has to not * match the one of another channel. If not, it could lead to spurious * flag status. */ u32 chan_cc = AT_XDMAC_CC_PERID(0x3f) | AT_XDMAC_CC_DAM_INCREMENTED_AM | AT_XDMAC_CC_SAM_INCREMENTED_AM | AT_XDMAC_CC_DIF(0) | AT_XDMAC_CC_SIF(0) | AT_XDMAC_CC_MBSIZE_SIXTEEN | AT_XDMAC_CC_TYPE_MEM_TRAN; unsigned long irqflags; dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n", __func__, &src, &dest, len, flags); if (unlikely(!len)) return NULL; dwidth = at_xdmac_align_width(chan, src_addr | dst_addr); /* Prepare descriptors. */ while (remaining_size) { struct at_xdmac_desc *desc = NULL; dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size); spin_lock_irqsave(&atchan->lock, irqflags); desc = at_xdmac_get_desc(atchan); spin_unlock_irqrestore(&atchan->lock, irqflags); if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) list_splice_init(&first->descs_list, &atchan->free_descs_list); return NULL; } /* Update src and dest addresses. */ src_addr += xfer_size; dst_addr += xfer_size; if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth) xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth; else xfer_size = remaining_size; dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size); /* Check remaining length and change data width if needed. */ dwidth = at_xdmac_align_width(chan, src_addr | dst_addr | xfer_size); chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK; chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth); ublen = xfer_size >> dwidth; remaining_size -= xfer_size; desc->lld.mbr_sa = src_addr; desc->lld.mbr_da = dst_addr; desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2 | AT_XDMAC_MBR_UBC_NDEN | AT_XDMAC_MBR_UBC_NSEN | ublen; desc->lld.mbr_cfg = chan_cc; dev_dbg(chan2dev(chan), "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n", __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg); /* Chain lld. */ if (prev) at_xdmac_queue_desc(chan, prev, desc); prev = desc; if (!first) first = desc; dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n", __func__, desc, first); list_add_tail(&desc->desc_node, &first->descs_list); } first->tx_dma_desc.flags = flags; first->xfer_size = len; return &first->tx_dma_desc; } static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan, struct at_xdmac_chan *atchan, dma_addr_t dst_addr, size_t len, int value) { struct at_xdmac_desc *desc; unsigned long flags; size_t ublen; u32 dwidth; /* * WARNING: The channel configuration is set here since there is no * dmaengine_slave_config call in this case. Moreover we don't know the * direction, it involves we can't dynamically set the source and dest * interface so we have to use the same one. Only interface 0 allows EBI * access. Hopefully we can access DDR through both ports (at least on * SAMA5D4x), so we can use the same interface for source and dest, * that solves the fact we don't know the direction. * ERRATA: Even if useless for memory transfers, the PERID has to not * match the one of another channel. If not, it could lead to spurious * flag status. */ u32 chan_cc = AT_XDMAC_CC_PERID(0x3f) | AT_XDMAC_CC_DAM_UBS_AM | AT_XDMAC_CC_SAM_INCREMENTED_AM | AT_XDMAC_CC_DIF(0) | AT_XDMAC_CC_SIF(0) | AT_XDMAC_CC_MBSIZE_SIXTEEN | AT_XDMAC_CC_MEMSET_HW_MODE | AT_XDMAC_CC_TYPE_MEM_TRAN; dwidth = at_xdmac_align_width(chan, dst_addr); if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) { dev_err(chan2dev(chan), "%s: Transfer too large, aborting...\n", __func__); return NULL; } spin_lock_irqsave(&atchan->lock, flags); desc = at_xdmac_get_desc(atchan); spin_unlock_irqrestore(&atchan->lock, flags); if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); return NULL; } chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth); ublen = len >> dwidth; desc->lld.mbr_da = dst_addr; desc->lld.mbr_ds = value; desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3 | AT_XDMAC_MBR_UBC_NDEN | AT_XDMAC_MBR_UBC_NSEN | ublen; desc->lld.mbr_cfg = chan_cc; dev_dbg(chan2dev(chan), "%s: lld: mbr_da=%pad, mbr_ds=0x%08x, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n", __func__, &desc->lld.mbr_da, desc->lld.mbr_ds, desc->lld.mbr_ubc, desc->lld.mbr_cfg); return desc; } static struct dma_async_tx_descriptor * at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac_desc *desc; dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n", __func__, &dest, len, value, flags); if (unlikely(!len)) return NULL; desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value); list_add_tail(&desc->desc_node, &desc->descs_list); desc->tx_dma_desc.cookie = -EBUSY; desc->tx_dma_desc.flags = flags; desc->xfer_size = len; return &desc->tx_dma_desc; } static struct dma_async_tx_descriptor * at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, int value, unsigned long flags) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac_desc *desc, *pdesc = NULL, *ppdesc = NULL, *first = NULL; struct scatterlist *sg, *psg = NULL, *ppsg = NULL; size_t stride = 0, pstride = 0, len = 0; int i; if (!sgl) return NULL; dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n", __func__, sg_len, value, flags); /* Prepare descriptors. */ for_each_sg(sgl, sg, sg_len, i) { dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n", __func__, &sg_dma_address(sg), sg_dma_len(sg), value, flags); desc = at_xdmac_memset_create_desc(chan, atchan, sg_dma_address(sg), sg_dma_len(sg), value); if (!desc && first) list_splice_init(&first->descs_list, &atchan->free_descs_list); if (!first) first = desc; /* Update our strides */ pstride = stride; if (psg) stride = sg_dma_address(sg) - (sg_dma_address(psg) + sg_dma_len(psg)); /* * The scatterlist API gives us only the address and * length of each elements. * * Unfortunately, we don't have the stride, which we * will need to compute. * * That make us end up in a situation like this one: * len stride len stride len * +-------+ +-------+ +-------+ * | N-2 | | N-1 | | N | * +-------+ +-------+ +-------+ * * We need all these three elements (N-2, N-1 and N) * to actually take the decision on whether we need to * queue N-1 or reuse N-2. * * We will only consider N if it is the last element. */ if (ppdesc && pdesc) { if ((stride == pstride) && (sg_dma_len(ppsg) == sg_dma_len(psg))) { dev_dbg(chan2dev(chan), "%s: desc 0x%p can be merged with desc 0x%p\n", __func__, pdesc, ppdesc); /* * Increment the block count of the * N-2 descriptor */ at_xdmac_increment_block_count(chan, ppdesc); ppdesc->lld.mbr_dus = stride; /* * Put back the N-1 descriptor in the * free descriptor list */ list_add_tail(&pdesc->desc_node, &atchan->free_descs_list); /* * Make our N-1 descriptor pointer * point to the N-2 since they were * actually merged. */ pdesc = ppdesc; /* * Rule out the case where we don't have * pstride computed yet (our second sg * element) * * We also want to catch the case where there * would be a negative stride, */ } else if (pstride || sg_dma_address(sg) < sg_dma_address(psg)) { /* * Queue the N-1 descriptor after the * N-2 */ at_xdmac_queue_desc(chan, ppdesc, pdesc); /* * Add the N-1 descriptor to the list * of the descriptors used for this * transfer */ list_add_tail(&desc->desc_node, &first->descs_list); dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n", __func__, desc, first); } } /* * If we are the last element, just see if we have the * same size than the previous element. * * If so, we can merge it with the previous descriptor * since we don't care about the stride anymore. */ if ((i == (sg_len - 1)) && sg_dma_len(psg) == sg_dma_len(sg)) { dev_dbg(chan2dev(chan), "%s: desc 0x%p can be merged with desc 0x%p\n", __func__, desc, pdesc); /* * Increment the block count of the N-1 * descriptor */ at_xdmac_increment_block_count(chan, pdesc); pdesc->lld.mbr_dus = stride; /* * Put back the N descriptor in the free * descriptor list */ list_add_tail(&desc->desc_node, &atchan->free_descs_list); } /* Update our descriptors */ ppdesc = pdesc; pdesc = desc; /* Update our scatter pointers */ ppsg = psg; psg = sg; len += sg_dma_len(sg); } first->tx_dma_desc.cookie = -EBUSY; first->tx_dma_desc.flags = flags; first->xfer_size = len; return &first->tx_dma_desc; } static enum dma_status at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device); struct at_xdmac_desc *desc, *_desc, *iter; struct list_head *descs_list; enum dma_status ret; int residue, retry; u32 cur_nda, check_nda, cur_ubc, mask, value; u8 dwidth = 0; unsigned long flags; bool initd; ret = dma_cookie_status(chan, cookie, txstate); if (ret == DMA_COMPLETE) return ret; if (!txstate) return ret; spin_lock_irqsave(&atchan->lock, flags); desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node); /* * If the transfer has not been started yet, don't need to compute the * residue, it's the transfer length. */ if (!desc->active_xfer) { dma_set_residue(txstate, desc->xfer_size); goto spin_unlock; } residue = desc->xfer_size; /* * Flush FIFO: only relevant when the transfer is source peripheral * synchronized. Flush is needed before reading CUBC because data in * the FIFO are not reported by CUBC. Reporting a residue of the * transfer length while we have data in FIFO can cause issue. * Usecase: atmel USART has a timeout which means I have received * characters but there is no more character received for a while. On * timeout, it requests the residue. If the data are in the DMA FIFO, * we will return a residue of the transfer length. It means no data * received. If an application is waiting for these data, it will hang * since we won't have another USART timeout without receiving new * data. */ mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC; value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM; if ((desc->lld.mbr_cfg & mask) == value) { at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask); while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS)) cpu_relax(); } /* * The easiest way to compute the residue should be to pause the DMA * but doing this can lead to miss some data as some devices don't * have FIFO. * We need to read several registers because: * - DMA is running therefore a descriptor change is possible while * reading these registers * - When the block transfer is done, the value of the CUBC register * is set to its initial value until the fetch of the next descriptor. * This value will corrupt the residue calculation so we have to skip * it. * * INITD -------- ------------ * |____________________| * _______________________ _______________ * NDA @desc2 \/ @desc3 * _______________________/\_______________ * __________ ___________ _______________ * CUBC 0 \/ MAX desc1 \/ MAX desc2 * __________/\___________/\_______________ * * Since descriptors are aligned on 64 bits, we can assume that * the update of NDA and CUBC is atomic. * Memory barriers are used to ensure the read order of the registers. * A max number of retries is set because unlikely it could never ends. */ for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) { check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc; rmb(); cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC); rmb(); initd = !!(at_xdmac_chan_read(atchan, AT_XDMAC_CC) & AT_XDMAC_CC_INITD); rmb(); cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc; rmb(); if ((check_nda == cur_nda) && initd) break; } if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) { ret = DMA_ERROR; goto spin_unlock; } /* * Flush FIFO: only relevant when the transfer is source peripheral * synchronized. Another flush is needed here because CUBC is updated * when the controller sends the data write command. It can lead to * report data that are not written in the memory or the device. The * FIFO flush ensures that data are really written. */ if ((desc->lld.mbr_cfg & mask) == value) { at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask); while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS)) cpu_relax(); } /* * Remove size of all microblocks already transferred and the current * one. Then add the remaining size to transfer of the current * microblock. */ descs_list = &desc->descs_list; list_for_each_entry_safe(iter, _desc, descs_list, desc_node) { dwidth = at_xdmac_get_dwidth(iter->lld.mbr_cfg); residue -= (iter->lld.mbr_ubc & 0xffffff) << dwidth; if ((iter->lld.mbr_nda & 0xfffffffc) == cur_nda) { desc = iter; break; } } residue += cur_ubc << dwidth; dma_set_residue(txstate, residue); dev_dbg(chan2dev(chan), "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n", __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue); spin_unlock: spin_unlock_irqrestore(&atchan->lock, flags); return ret; } /* Call must be protected by lock. */ static void at_xdmac_remove_xfer(struct at_xdmac_chan *atchan, struct at_xdmac_desc *desc) { dev_dbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc); /* * Remove the transfer from the transfer list then move the transfer * descriptors into the free descriptors list. */ list_del(&desc->xfer_node); list_splice_init(&desc->descs_list, &atchan->free_descs_list); } static void at_xdmac_advance_work(struct at_xdmac_chan *atchan) { struct at_xdmac_desc *desc; unsigned long flags; spin_lock_irqsave(&atchan->lock, flags); /* * If channel is enabled, do nothing, advance_work will be triggered * after the interruption. */ if (!at_xdmac_chan_is_enabled(atchan) && !list_empty(&atchan->xfers_list)) { desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node); dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc); if (!desc->active_xfer) at_xdmac_start_xfer(atchan, desc); } spin_unlock_irqrestore(&atchan->lock, flags); } static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan) { struct at_xdmac_desc *desc; struct dma_async_tx_descriptor *txd; desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node); txd = &desc->tx_dma_desc; if (txd->flags & DMA_PREP_INTERRUPT) dmaengine_desc_get_callback_invoke(txd, NULL); } static void at_xdmac_tasklet(unsigned long data) { struct at_xdmac_chan *atchan = (struct at_xdmac_chan *)data; struct at_xdmac_desc *desc; u32 error_mask; dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n", __func__, atchan->irq_status); error_mask = AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS | AT_XDMAC_CIS_ROIS; if (at_xdmac_chan_is_cyclic(atchan)) { at_xdmac_handle_cyclic(atchan); } else if ((atchan->irq_status & AT_XDMAC_CIS_LIS) || (atchan->irq_status & error_mask)) { struct dma_async_tx_descriptor *txd; if (atchan->irq_status & AT_XDMAC_CIS_RBEIS) dev_err(chan2dev(&atchan->chan), "read bus error!!!"); if (atchan->irq_status & AT_XDMAC_CIS_WBEIS) dev_err(chan2dev(&atchan->chan), "write bus error!!!"); if (atchan->irq_status & AT_XDMAC_CIS_ROIS) dev_err(chan2dev(&atchan->chan), "request overflow error!!!"); spin_lock_bh(&atchan->lock); desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node); dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc); if (!desc->active_xfer) { dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting"); spin_unlock_bh(&atchan->lock); return; } txd = &desc->tx_dma_desc; at_xdmac_remove_xfer(atchan, desc); spin_unlock_bh(&atchan->lock); if (!at_xdmac_chan_is_cyclic(atchan)) { dma_cookie_complete(txd); if (txd->flags & DMA_PREP_INTERRUPT) dmaengine_desc_get_callback_invoke(txd, NULL); } dma_run_dependencies(txd); at_xdmac_advance_work(atchan); } } static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id) { struct at_xdmac *atxdmac = (struct at_xdmac *)dev_id; struct at_xdmac_chan *atchan; u32 imr, status, pending; u32 chan_imr, chan_status; int i, ret = IRQ_NONE; do { imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM); status = at_xdmac_read(atxdmac, AT_XDMAC_GIS); pending = status & imr; dev_vdbg(atxdmac->dma.dev, "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n", __func__, status, imr, pending); if (!pending) break; /* We have to find which channel has generated the interrupt. */ for (i = 0; i < atxdmac->dma.chancnt; i++) { if (!((1 << i) & pending)) continue; atchan = &atxdmac->chan[i]; chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM); chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS); atchan->irq_status = chan_status & chan_imr; dev_vdbg(atxdmac->dma.dev, "%s: chan%d: imr=0x%x, status=0x%x\n", __func__, i, chan_imr, chan_status); dev_vdbg(chan2dev(&atchan->chan), "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n", __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC), at_xdmac_chan_read(atchan, AT_XDMAC_CNDA), at_xdmac_chan_read(atchan, AT_XDMAC_CNDC), at_xdmac_chan_read(atchan, AT_XDMAC_CSA), at_xdmac_chan_read(atchan, AT_XDMAC_CDA), at_xdmac_chan_read(atchan, AT_XDMAC_CUBC)); if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS)) at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask); tasklet_schedule(&atchan->tasklet); ret = IRQ_HANDLED; } } while (pending); return ret; } static void at_xdmac_issue_pending(struct dma_chan *chan) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__); if (!at_xdmac_chan_is_cyclic(atchan)) at_xdmac_advance_work(atchan); return; } static int at_xdmac_device_config(struct dma_chan *chan, struct dma_slave_config *config) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); int ret; unsigned long flags; dev_dbg(chan2dev(chan), "%s\n", __func__); spin_lock_irqsave(&atchan->lock, flags); ret = at_xdmac_set_slave_config(chan, config); spin_unlock_irqrestore(&atchan->lock, flags); return ret; } static int at_xdmac_device_pause(struct dma_chan *chan) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device); unsigned long flags; dev_dbg(chan2dev(chan), "%s\n", __func__); if (test_and_set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status)) return 0; spin_lock_irqsave(&atchan->lock, flags); at_xdmac_write(atxdmac, AT_XDMAC_GRWS, atchan->mask); while (at_xdmac_chan_read(atchan, AT_XDMAC_CC) & (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP)) cpu_relax(); spin_unlock_irqrestore(&atchan->lock, flags); return 0; } static int at_xdmac_device_resume(struct dma_chan *chan) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device); unsigned long flags; dev_dbg(chan2dev(chan), "%s\n", __func__); spin_lock_irqsave(&atchan->lock, flags); if (!at_xdmac_chan_is_paused(atchan)) { spin_unlock_irqrestore(&atchan->lock, flags); return 0; } at_xdmac_write(atxdmac, AT_XDMAC_GRWR, atchan->mask); clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status); spin_unlock_irqrestore(&atchan->lock, flags); return 0; } static int at_xdmac_device_terminate_all(struct dma_chan *chan) { struct at_xdmac_desc *desc, *_desc; struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device); unsigned long flags; dev_dbg(chan2dev(chan), "%s\n", __func__); spin_lock_irqsave(&atchan->lock, flags); at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask); while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask) cpu_relax(); /* Cancel all pending transfers. */ list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) at_xdmac_remove_xfer(atchan, desc); clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status); clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status); spin_unlock_irqrestore(&atchan->lock, flags); return 0; } static int at_xdmac_alloc_chan_resources(struct dma_chan *chan) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac_desc *desc; int i; unsigned long flags; spin_lock_irqsave(&atchan->lock, flags); if (at_xdmac_chan_is_enabled(atchan)) { dev_err(chan2dev(chan), "can't allocate channel resources (channel enabled)\n"); i = -EIO; goto spin_unlock; } if (!list_empty(&atchan->free_descs_list)) { dev_err(chan2dev(chan), "can't allocate channel resources (channel not free from a previous use)\n"); i = -EIO; goto spin_unlock; } for (i = 0; i < init_nr_desc_per_channel; i++) { desc = at_xdmac_alloc_desc(chan, GFP_ATOMIC); if (!desc) { if (i == 0) { dev_warn(chan2dev(chan), "can't allocate any descriptors\n"); return -EIO; } dev_warn(chan2dev(chan), "only %d descriptors have been allocated\n", i); break; } list_add_tail(&desc->desc_node, &atchan->free_descs_list); } dma_cookie_init(chan); dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i); spin_unlock: spin_unlock_irqrestore(&atchan->lock, flags); return i; } static void at_xdmac_free_chan_resources(struct dma_chan *chan) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac *atxdmac = to_at_xdmac(chan->device); struct at_xdmac_desc *desc, *_desc; list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) { dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc); list_del(&desc->desc_node); dma_pool_free(atxdmac->at_xdmac_desc_pool, desc, desc->tx_dma_desc.phys); } return; } #ifdef CONFIG_PM static int atmel_xdmac_prepare(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct at_xdmac *atxdmac = platform_get_drvdata(pdev); struct dma_chan *chan, *_chan; list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); /* Wait for transfer completion, except in cyclic case. */ if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan)) return -EAGAIN; } return 0; } #else # define atmel_xdmac_prepare NULL #endif #ifdef CONFIG_PM_SLEEP static int atmel_xdmac_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct at_xdmac *atxdmac = platform_get_drvdata(pdev); struct dma_chan *chan, *_chan; list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC); if (at_xdmac_chan_is_cyclic(atchan)) { if (!at_xdmac_chan_is_paused(atchan)) at_xdmac_device_pause(chan); atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM); atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA); atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC); } } atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM); at_xdmac_off(atxdmac); clk_disable_unprepare(atxdmac->clk); return 0; } static int atmel_xdmac_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct at_xdmac *atxdmac = platform_get_drvdata(pdev); struct at_xdmac_chan *atchan; struct dma_chan *chan, *_chan; int i; clk_prepare_enable(atxdmac->clk); /* Clear pending interrupts. */ for (i = 0; i < atxdmac->dma.chancnt; i++) { atchan = &atxdmac->chan[i]; while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS)) cpu_relax(); } at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim); at_xdmac_write(atxdmac, AT_XDMAC_GE, atxdmac->save_gs); list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) { atchan = to_at_xdmac_chan(chan); at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc); if (at_xdmac_chan_is_cyclic(atchan)) { if (at_xdmac_chan_is_paused(atchan)) at_xdmac_device_resume(chan); at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda); at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc); at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim); wmb(); at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask); } } return 0; } #endif /* CONFIG_PM_SLEEP */ static int at_xdmac_probe(struct platform_device *pdev) { struct resource *res; struct at_xdmac *atxdmac; int irq, size, nr_channels, i, ret; void __iomem *base; u32 reg; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -EINVAL; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(base)) return PTR_ERR(base); /* * Read number of xdmac channels, read helper function can't be used * since atxdmac is not yet allocated and we need to know the number * of channels to do the allocation. */ reg = readl_relaxed(base + AT_XDMAC_GTYPE); nr_channels = AT_XDMAC_NB_CH(reg); if (nr_channels > AT_XDMAC_MAX_CHAN) { dev_err(&pdev->dev, "invalid number of channels (%u)\n", nr_channels); return -EINVAL; } size = sizeof(*atxdmac); size += nr_channels * sizeof(struct at_xdmac_chan); atxdmac = devm_kzalloc(&pdev->dev, size, GFP_KERNEL); if (!atxdmac) { dev_err(&pdev->dev, "can't allocate at_xdmac structure\n"); return -ENOMEM; } atxdmac->regs = base; atxdmac->irq = irq; atxdmac->clk = devm_clk_get(&pdev->dev, "dma_clk"); if (IS_ERR(atxdmac->clk)) { dev_err(&pdev->dev, "can't get dma_clk\n"); return PTR_ERR(atxdmac->clk); } /* Do not use dev res to prevent races with tasklet */ ret = request_irq(atxdmac->irq, at_xdmac_interrupt, 0, "at_xdmac", atxdmac); if (ret) { dev_err(&pdev->dev, "can't request irq\n"); return ret; } ret = clk_prepare_enable(atxdmac->clk); if (ret) { dev_err(&pdev->dev, "can't prepare or enable clock\n"); goto err_free_irq; } atxdmac->at_xdmac_desc_pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev, sizeof(struct at_xdmac_desc), 4, 0); if (!atxdmac->at_xdmac_desc_pool) { dev_err(&pdev->dev, "no memory for descriptors dma pool\n"); ret = -ENOMEM; goto err_clk_disable; } dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask); dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask); dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask); dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask); dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask); dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask); /* * Without DMA_PRIVATE the driver is not able to allocate more than * one channel, second allocation fails in private_candidate. */ dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask); atxdmac->dma.dev = &pdev->dev; atxdmac->dma.device_alloc_chan_resources = at_xdmac_alloc_chan_resources; atxdmac->dma.device_free_chan_resources = at_xdmac_free_chan_resources; atxdmac->dma.device_tx_status = at_xdmac_tx_status; atxdmac->dma.device_issue_pending = at_xdmac_issue_pending; atxdmac->dma.device_prep_dma_cyclic = at_xdmac_prep_dma_cyclic; atxdmac->dma.device_prep_interleaved_dma = at_xdmac_prep_interleaved; atxdmac->dma.device_prep_dma_memcpy = at_xdmac_prep_dma_memcpy; atxdmac->dma.device_prep_dma_memset = at_xdmac_prep_dma_memset; atxdmac->dma.device_prep_dma_memset_sg = at_xdmac_prep_dma_memset_sg; atxdmac->dma.device_prep_slave_sg = at_xdmac_prep_slave_sg; atxdmac->dma.device_config = at_xdmac_device_config; atxdmac->dma.device_pause = at_xdmac_device_pause; atxdmac->dma.device_resume = at_xdmac_device_resume; atxdmac->dma.device_terminate_all = at_xdmac_device_terminate_all; atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS; atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS; atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; /* Disable all chans and interrupts. */ at_xdmac_off(atxdmac); /* Init channels. */ INIT_LIST_HEAD(&atxdmac->dma.channels); for (i = 0; i < nr_channels; i++) { struct at_xdmac_chan *atchan = &atxdmac->chan[i]; atchan->chan.device = &atxdmac->dma; list_add_tail(&atchan->chan.device_node, &atxdmac->dma.channels); atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, i); atchan->mask = 1 << i; spin_lock_init(&atchan->lock); INIT_LIST_HEAD(&atchan->xfers_list); INIT_LIST_HEAD(&atchan->free_descs_list); tasklet_init(&atchan->tasklet, at_xdmac_tasklet, (unsigned long)atchan); /* Clear pending interrupts. */ while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS)) cpu_relax(); } platform_set_drvdata(pdev, atxdmac); ret = dma_async_device_register(&atxdmac->dma); if (ret) { dev_err(&pdev->dev, "fail to register DMA engine device\n"); goto err_clk_disable; } ret = of_dma_controller_register(pdev->dev.of_node, at_xdmac_xlate, atxdmac); if (ret) { dev_err(&pdev->dev, "could not register of dma controller\n"); goto err_dma_unregister; } dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n", nr_channels, atxdmac->regs); return 0; err_dma_unregister: dma_async_device_unregister(&atxdmac->dma); err_clk_disable: clk_disable_unprepare(atxdmac->clk); err_free_irq: free_irq(atxdmac->irq, atxdmac); return ret; } static int at_xdmac_remove(struct platform_device *pdev) { struct at_xdmac *atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev); int i; at_xdmac_off(atxdmac); of_dma_controller_free(pdev->dev.of_node); dma_async_device_unregister(&atxdmac->dma); clk_disable_unprepare(atxdmac->clk); free_irq(atxdmac->irq, atxdmac); for (i = 0; i < atxdmac->dma.chancnt; i++) { struct at_xdmac_chan *atchan = &atxdmac->chan[i]; tasklet_kill(&atchan->tasklet); at_xdmac_free_chan_resources(&atchan->chan); } return 0; } static const struct dev_pm_ops atmel_xdmac_dev_pm_ops = { .prepare = atmel_xdmac_prepare, SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume) }; static const struct of_device_id atmel_xdmac_dt_ids[] = { { .compatible = "atmel,sama5d4-dma", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids); static struct platform_driver at_xdmac_driver = { .probe = at_xdmac_probe, .remove = at_xdmac_remove, .driver = { .name = "at_xdmac", .of_match_table = of_match_ptr(atmel_xdmac_dt_ids), .pm = &atmel_xdmac_dev_pm_ops, } }; static int __init at_xdmac_init(void) { return platform_driver_probe(&at_xdmac_driver, at_xdmac_probe); } subsys_initcall(at_xdmac_init); MODULE_DESCRIPTION("Atmel Extended DMA Controller driver"); MODULE_AUTHOR("Ludovic Desroches "); MODULE_LICENSE("GPL");