/* $Id: iommu.c,v 1.21 2001/02/13 01:16:43 davem Exp $ * iommu.c: IOMMU specific routines for memory management. * * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) * Copyright (C) 1995 Pete Zaitcev * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) */ #include #include #include #include #include #include #include #include #include #include #include #include /* srmmu.c */ extern int viking_mxcc_present; BTFIXUPDEF_CALL(void, flush_page_for_dma, unsigned long) #define flush_page_for_dma(page) BTFIXUP_CALL(flush_page_for_dma)(page) extern int flush_page_for_dma_global; static int viking_flush = 0; /* viking.S */ extern void viking_flush_page(unsigned long page); extern void viking_mxcc_flush_page(unsigned long page); #define IOPERM (IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID) #define MKIOPTE(phys) (((((phys)>>4) & IOPTE_PAGE) | IOPERM) & ~IOPTE_WAZ) static inline void iommu_map_dvma_pages_for_iommu(struct iommu_struct *iommu) { unsigned long kern_end = (unsigned long) high_memory; unsigned long first = PAGE_OFFSET; unsigned long last = kern_end; iopte_t *iopte = iommu->page_table; iopte += ((first - iommu->start) >> PAGE_SHIFT); while(first <= last) { *iopte++ = __iopte(MKIOPTE(__pa(first))); first += PAGE_SIZE; } } void __init iommu_init(int iommund, struct sbus_bus *sbus) { unsigned int impl, vers, ptsize; unsigned long tmp; struct iommu_struct *iommu; struct linux_prom_registers iommu_promregs[PROMREG_MAX]; struct resource r; int i; iommu = kmalloc(sizeof(struct iommu_struct), GFP_ATOMIC); prom_getproperty(iommund, "reg", (void *) iommu_promregs, sizeof(iommu_promregs)); memset(&r, 0, sizeof(r)); r.flags = iommu_promregs[0].which_io; r.start = iommu_promregs[0].phys_addr; iommu->regs = (struct iommu_regs *) sbus_ioremap(&r, 0, PAGE_SIZE * 3, "iommu_regs"); if(!iommu->regs) panic("Cannot map IOMMU registers."); impl = (iommu->regs->control & IOMMU_CTRL_IMPL) >> 28; vers = (iommu->regs->control & IOMMU_CTRL_VERS) >> 24; tmp = iommu->regs->control; tmp &= ~(IOMMU_CTRL_RNGE); switch(PAGE_OFFSET & 0xf0000000) { case 0xf0000000: tmp |= (IOMMU_RNGE_256MB | IOMMU_CTRL_ENAB); iommu->plow = iommu->start = 0xf0000000; break; case 0xe0000000: tmp |= (IOMMU_RNGE_512MB | IOMMU_CTRL_ENAB); iommu->plow = iommu->start = 0xe0000000; break; case 0xd0000000: case 0xc0000000: tmp |= (IOMMU_RNGE_1GB | IOMMU_CTRL_ENAB); iommu->plow = iommu->start = 0xc0000000; break; case 0xb0000000: case 0xa0000000: case 0x90000000: case 0x80000000: tmp |= (IOMMU_RNGE_2GB | IOMMU_CTRL_ENAB); iommu->plow = iommu->start = 0x80000000; break; } iommu->regs->control = tmp; iommu_invalidate(iommu->regs); iommu->end = 0xffffffff; /* Allocate IOMMU page table */ ptsize = iommu->end - iommu->start + 1; ptsize = (ptsize >> PAGE_SHIFT) * sizeof(iopte_t); /* Stupid alignment constraints give me a headache. We need 256K or 512K or 1M or 2M area aligned to its size and current gfp will fortunately give it to us. */ for (i = 6; i < 9; i++) if ((1 << (i + PAGE_SHIFT)) == ptsize) break; tmp = __get_free_pages(GFP_DMA, i); if (!tmp) { prom_printf("Could not allocate iopte of size 0x%08x\n", ptsize); prom_halt(); } iommu->lowest = iommu->page_table = (iopte_t *)tmp; /* Initialize new table. */ flush_cache_all(); memset(iommu->page_table, 0, ptsize); iommu_map_dvma_pages_for_iommu(iommu); if(viking_mxcc_present) { unsigned long start = (unsigned long) iommu->page_table; unsigned long end = (start + ptsize); while(start < end) { viking_mxcc_flush_page(start); start += PAGE_SIZE; } } else if (viking_flush) { unsigned long start = (unsigned long) iommu->page_table; unsigned long end = (start + ptsize); while(start < end) { viking_flush_page(start); start += PAGE_SIZE; } } flush_tlb_all(); iommu->regs->base = __pa((unsigned long) iommu->page_table) >> 4; iommu_invalidate(iommu->regs); sbus->iommu = iommu; printk("IOMMU: impl %d vers %d page table at %p of size %d bytes\n", impl, vers, iommu->page_table, ptsize); } static __u32 iommu_get_scsi_one_noflush(char *vaddr, unsigned long len, struct sbus_bus *sbus) { return (__u32)vaddr; } static __u32 iommu_get_scsi_one_gflush(char *vaddr, unsigned long len, struct sbus_bus *sbus) { flush_page_for_dma(0); return (__u32)vaddr; } static __u32 iommu_get_scsi_one_pflush(char *vaddr, unsigned long len, struct sbus_bus *sbus) { unsigned long page = ((unsigned long) vaddr) & PAGE_MASK; while(page < ((unsigned long)(vaddr + len))) { flush_page_for_dma(page); page += PAGE_SIZE; } return (__u32)vaddr; } static void iommu_get_scsi_sgl_noflush(struct scatterlist *sg, int sz, struct sbus_bus *sbus) { for (; sz >= 0; sz--) { sg[sz].dvma_address = (__u32) (sg[sz].address); sg[sz].dvma_length = (__u32) (sg[sz].length); } } static void iommu_get_scsi_sgl_gflush(struct scatterlist *sg, int sz, struct sbus_bus *sbus) { flush_page_for_dma(0); for (; sz >= 0; sz--) { sg[sz].dvma_address = (__u32) (sg[sz].address); sg[sz].dvma_length = (__u32) (sg[sz].length); } } static void iommu_get_scsi_sgl_pflush(struct scatterlist *sg, int sz, struct sbus_bus *sbus) { unsigned long page, oldpage = 0; while(sz >= 0) { page = ((unsigned long) sg[sz].address) & PAGE_MASK; if (oldpage == page) page += PAGE_SIZE; /* We flushed that page already */ while(page < (unsigned long)(sg[sz].address + sg[sz].length)) { flush_page_for_dma(page); page += PAGE_SIZE; } sg[sz].dvma_address = (__u32) (sg[sz].address); sg[sz].dvma_length = (__u32) (sg[sz].length); sz--; oldpage = page - PAGE_SIZE; } } static void iommu_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus) { } static void iommu_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus) { } #ifdef CONFIG_SBUS static void iommu_map_dma_area(unsigned long va, __u32 addr, int len) { unsigned long page, end, ipte_cache; pgprot_t dvma_prot; struct iommu_struct *iommu = sbus_root->iommu; iopte_t *iopte = iommu->page_table; iopte_t *first; if(viking_mxcc_present || srmmu_modtype == HyperSparc) { dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV); ipte_cache = 1; } else { dvma_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV); ipte_cache = 0; } iopte += ((addr - iommu->start) >> PAGE_SHIFT); first = iopte; end = PAGE_ALIGN((addr + len)); while(addr < end) { page = va; { pgd_t *pgdp; pmd_t *pmdp; pte_t *ptep; if (viking_mxcc_present) viking_mxcc_flush_page(page); else if (viking_flush) viking_flush_page(page); else __flush_page_to_ram(page); pgdp = pgd_offset(&init_mm, addr); pmdp = pmd_offset(pgdp, addr); ptep = pte_offset(pmdp, addr); set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot)); if (ipte_cache != 0) { iopte_val(*iopte++) = MKIOPTE(__pa(page)); } else { iopte_val(*iopte++) = MKIOPTE(__pa(page)) & ~IOPTE_CACHE; } } addr += PAGE_SIZE; va += PAGE_SIZE; } /* P3: why do we need this? * * DAVEM: Because there are several aspects, none of which * are handled by a single interface. Some cpus are * completely not I/O DMA coherent, and some have * virtually indexed caches. The driver DMA flushing * methods handle the former case, but here during * IOMMU page table modifications, and usage of non-cacheable * cpu mappings of pages potentially in the cpu caches, we have * to handle the latter case as well. */ flush_cache_all(); if(viking_mxcc_present) { unsigned long start = ((unsigned long) first) & PAGE_MASK; unsigned long end = PAGE_ALIGN(((unsigned long) iopte)); while(start < end) { viking_mxcc_flush_page(start); start += PAGE_SIZE; } } else if(viking_flush) { unsigned long start = ((unsigned long) first) & PAGE_MASK; unsigned long end = PAGE_ALIGN(((unsigned long) iopte)); while(start < end) { viking_flush_page(start); start += PAGE_SIZE; } } flush_tlb_all(); iommu_invalidate(iommu->regs); } static void iommu_unmap_dma_area(unsigned long busa, int len) { struct iommu_struct *iommu = sbus_root->iommu; iopte_t *iopte = iommu->page_table; unsigned long end; iopte += ((busa - iommu->start) >> PAGE_SHIFT); end = PAGE_ALIGN((busa + len)); while (busa < end) { iopte_val(*iopte++) = 0; busa += PAGE_SIZE; } flush_tlb_all(); /* P3: Hmm... it would not hurt. */ iommu_invalidate(iommu->regs); } static unsigned long iommu_translate_dvma(unsigned long busa) { struct iommu_struct *iommu = sbus_root->iommu; iopte_t *iopte = iommu->page_table; unsigned long pa; iopte += ((busa - iommu->start) >> PAGE_SHIFT); pa = pte_val(*iopte); pa = (pa & 0xFFFFFFF0) << 4; /* Loose higher bits of 36 */ return pa + PAGE_OFFSET; } #endif static char *iommu_lockarea(char *vaddr, unsigned long len) { return vaddr; } static void iommu_unlockarea(char *vaddr, unsigned long len) { } void __init ld_mmu_iommu(void) { viking_flush = (BTFIXUPVAL_CALL(flush_page_for_dma) == (unsigned long)viking_flush_page); BTFIXUPSET_CALL(mmu_lockarea, iommu_lockarea, BTFIXUPCALL_RETO0); BTFIXUPSET_CALL(mmu_unlockarea, iommu_unlockarea, BTFIXUPCALL_NOP); if (!BTFIXUPVAL_CALL(flush_page_for_dma)) { /* IO coherent chip */ BTFIXUPSET_CALL(mmu_get_scsi_one, iommu_get_scsi_one_noflush, BTFIXUPCALL_RETO0); BTFIXUPSET_CALL(mmu_get_scsi_sgl, iommu_get_scsi_sgl_noflush, BTFIXUPCALL_NORM); } else if (flush_page_for_dma_global) { /* flush_page_for_dma flushes everything, no matter of what page is it */ BTFIXUPSET_CALL(mmu_get_scsi_one, iommu_get_scsi_one_gflush, BTFIXUPCALL_NORM); BTFIXUPSET_CALL(mmu_get_scsi_sgl, iommu_get_scsi_sgl_gflush, BTFIXUPCALL_NORM); } else { BTFIXUPSET_CALL(mmu_get_scsi_one, iommu_get_scsi_one_pflush, BTFIXUPCALL_NORM); BTFIXUPSET_CALL(mmu_get_scsi_sgl, iommu_get_scsi_sgl_pflush, BTFIXUPCALL_NORM); } BTFIXUPSET_CALL(mmu_release_scsi_one, iommu_release_scsi_one, BTFIXUPCALL_NOP); BTFIXUPSET_CALL(mmu_release_scsi_sgl, iommu_release_scsi_sgl, BTFIXUPCALL_NOP); #ifdef CONFIG_SBUS BTFIXUPSET_CALL(mmu_map_dma_area, iommu_map_dma_area, BTFIXUPCALL_NORM); BTFIXUPSET_CALL(mmu_unmap_dma_area, iommu_unmap_dma_area, BTFIXUPCALL_NORM); BTFIXUPSET_CALL(mmu_translate_dvma, iommu_translate_dvma, BTFIXUPCALL_NORM); #endif }