--- zzzz-none-000/linux-3.10.107/arch/arm/kernel/head-nommu.S 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/arch/arm/kernel/head-nommu.S 2021-02-04 17:41:59.000000000 +0000 @@ -17,8 +17,12 @@ #include #include #include +#include #include #include +#include +#include +#include /* * Kernel startup entry point. @@ -42,7 +46,7 @@ .arm ENTRY(stext) - THUMB( adr r9, BSYM(1f) ) @ Kernel is always entered in ARM. + THUMB( badr r9, 1f ) @ Kernel is always entered in ARM. THUMB( bx r9 ) @ If this is a Thumb-2 kernel, THUMB( .thumb ) @ switch to Thumb now. THUMB(1: ) @@ -50,21 +54,81 @@ setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode @ and irqs disabled -#ifndef CONFIG_CPU_CP15 - ldr r9, =CONFIG_PROCESSOR_ID -#else +#if defined(CONFIG_CPU_CP15) mrc p15, 0, r9, c0, c0 @ get processor id +#elif defined(CONFIG_CPU_V7M) + ldr r9, =BASEADDR_V7M_SCB + ldr r9, [r9, V7M_SCB_CPUID] +#else + ldr r9, =CONFIG_PROCESSOR_ID #endif bl __lookup_processor_type @ r5=procinfo r9=cpuid movs r10, r5 @ invalid processor (r5=0)? beq __error_p @ yes, error 'p' - adr lr, BSYM(__after_proc_init) @ return (PIC) address - ARM( add pc, r10, #PROCINFO_INITFUNC ) - THUMB( add r12, r10, #PROCINFO_INITFUNC ) - THUMB( mov pc, r12 ) +#ifdef CONFIG_ARM_MPU + /* Calculate the size of a region covering just the kernel */ + ldr r5, =PLAT_PHYS_OFFSET @ Region start: PHYS_OFFSET + ldr r6, =(_end) @ Cover whole kernel + sub r6, r6, r5 @ Minimum size of region to map + clz r6, r6 @ Region size must be 2^N... + rsb r6, r6, #31 @ ...so round up region size + lsl r6, r6, #MPU_RSR_SZ @ Put size in right field + orr r6, r6, #(1 << MPU_RSR_EN) @ Set region enabled bit + bl __setup_mpu +#endif + + badr lr, 1f @ return (PIC) address + ldr r12, [r10, #PROCINFO_INITFUNC] + add r12, r12, r10 + ret r12 +1: bl __after_proc_init + b __mmap_switched ENDPROC(stext) +#ifdef CONFIG_SMP + .text +ENTRY(secondary_startup) + /* + * Common entry point for secondary CPUs. + * + * Ensure that we're in SVC mode, and IRQs are disabled. Lookup + * the processor type - there is no need to check the machine type + * as it has already been validated by the primary processor. + */ + setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 +#ifndef CONFIG_CPU_CP15 + ldr r9, =CONFIG_PROCESSOR_ID +#else + mrc p15, 0, r9, c0, c0 @ get processor id +#endif + bl __lookup_processor_type @ r5=procinfo r9=cpuid + movs r10, r5 @ invalid processor? + beq __error_p @ yes, error 'p' + + ldr r7, __secondary_data + +#ifdef CONFIG_ARM_MPU + /* Use MPU region info supplied by __cpu_up */ + ldr r6, [r7] @ get secondary_data.mpu_szr + bl __setup_mpu @ Initialize the MPU +#endif + + badr lr, 1f @ return (PIC) address + ldr r12, [r10, #PROCINFO_INITFUNC] + add r12, r12, r10 + ret r12 +1: bl __after_proc_init + ldr sp, [r7, #12] @ set up the stack pointer + mov fp, #0 + b secondary_start_kernel +ENDPROC(secondary_startup) + + .type __secondary_data, %object +__secondary_data: + .long secondary_data +#endif /* CONFIG_SMP */ + /* * Set the Control Register and Read the process ID. */ @@ -95,10 +159,97 @@ #endif mcr p15, 0, r0, c1, c0, 0 @ write control reg #endif /* CONFIG_CPU_CP15 */ - - b __mmap_switched @ clear the BSS and jump - @ to start_kernel + ret lr ENDPROC(__after_proc_init) .ltorg +#ifdef CONFIG_ARM_MPU + + +/* Set which MPU region should be programmed */ +.macro set_region_nr tmp, rgnr + mov \tmp, \rgnr @ Use static region numbers + mcr p15, 0, \tmp, c6, c2, 0 @ Write RGNR +.endm + +/* Setup a single MPU region, either D or I side (D-side for unified) */ +.macro setup_region bar, acr, sr, side = MPU_DATA_SIDE + mcr p15, 0, \bar, c6, c1, (0 + \side) @ I/DRBAR + mcr p15, 0, \acr, c6, c1, (4 + \side) @ I/DRACR + mcr p15, 0, \sr, c6, c1, (2 + \side) @ I/DRSR +.endm + +/* + * Setup the MPU and initial MPU Regions. We create the following regions: + * Region 0: Use this for probing the MPU details, so leave disabled. + * Region 1: Background region - covers the whole of RAM as strongly ordered + * Region 2: Normal, Shared, cacheable for RAM. From PHYS_OFFSET, size from r6 + * Region 3: Normal, shared, inaccessible from PL0 to protect the vectors page + * + * r6: Value to be written to DRSR (and IRSR if required) for MPU_RAM_REGION +*/ + +ENTRY(__setup_mpu) + + /* Probe for v7 PMSA compliance */ + mrc p15, 0, r0, c0, c1, 4 @ Read ID_MMFR0 + and r0, r0, #(MMFR0_PMSA) @ PMSA field + teq r0, #(MMFR0_PMSAv7) @ PMSA v7 + bne __error_p @ Fail: ARM_MPU on NOT v7 PMSA + + /* Determine whether the D/I-side memory map is unified. We set the + * flags here and continue to use them for the rest of this function */ + mrc p15, 0, r0, c0, c0, 4 @ MPUIR + ands r5, r0, #MPUIR_DREGION_SZMASK @ 0 size d region => No MPU + beq __error_p @ Fail: ARM_MPU and no MPU + tst r0, #MPUIR_nU @ MPUIR_nU = 0 for unified + + /* Setup second region first to free up r6 */ + set_region_nr r0, #MPU_RAM_REGION + isb + /* Full access from PL0, PL1, shared for CONFIG_SMP, cacheable */ + ldr r0, =PLAT_PHYS_OFFSET @ RAM starts at PHYS_OFFSET + ldr r5,=(MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL) + + setup_region r0, r5, r6, MPU_DATA_SIDE @ PHYS_OFFSET, shared, enabled + beq 1f @ Memory-map not unified + setup_region r0, r5, r6, MPU_INSTR_SIDE @ PHYS_OFFSET, shared, enabled +1: isb + + /* First/background region */ + set_region_nr r0, #MPU_BG_REGION + isb + /* Execute Never, strongly ordered, inaccessible to PL0, rw PL1 */ + mov r0, #0 @ BG region starts at 0x0 + ldr r5,=(MPU_ACR_XN | MPU_RGN_STRONGLY_ORDERED | MPU_AP_PL1RW_PL0NA) + mov r6, #MPU_RSR_ALL_MEM @ 4GB region, enabled + + setup_region r0, r5, r6, MPU_DATA_SIDE @ 0x0, BG region, enabled + beq 2f @ Memory-map not unified + setup_region r0, r5, r6, MPU_INSTR_SIDE @ 0x0, BG region, enabled +2: isb + + /* Vectors region */ + set_region_nr r0, #MPU_VECTORS_REGION + isb + /* Shared, inaccessible to PL0, rw PL1 */ + mov r0, #CONFIG_VECTORS_BASE @ Cover from VECTORS_BASE + ldr r5,=(MPU_AP_PL1RW_PL0NA | MPU_RGN_NORMAL) + /* Writing N to bits 5:1 (RSR_SZ) --> region size 2^N+1 */ + mov r6, #(((PAGE_SHIFT - 1) << MPU_RSR_SZ) | 1 << MPU_RSR_EN) + + setup_region r0, r5, r6, MPU_DATA_SIDE @ VECTORS_BASE, PL0 NA, enabled + beq 3f @ Memory-map not unified + setup_region r0, r5, r6, MPU_INSTR_SIDE @ VECTORS_BASE, PL0 NA, enabled +3: isb + + /* Enable the MPU */ + mrc p15, 0, r0, c1, c0, 0 @ Read SCTLR + bic r0, r0, #CR_BR @ Disable the 'default mem-map' + orr r0, r0, #CR_M @ Set SCTRL.M (MPU on) + mcr p15, 0, r0, c1, c0, 0 @ Enable MPU + isb + ret lr +ENDPROC(__setup_mpu) +#endif #include "head-common.S"