[ARM] armv7: add support for ARMv7 cores.

This patch adds support for the ARMv7 cores.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

4 files changed, 559 insertions, 0 deletions

diff --git a/arch/arm/mm/abort-ev7.S b/arch/arm/mm/abort-ev7.S
new file mode 100644
index 000000000000..eb90bce38e14
--- /dev/null
+++ b/arch/arm/mm/abort-ev7.S
@@ -0,0 +1,32 @@
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+/*
+ * Function: v7_early_abort
+ *
+ * Params  : r2 = address of aborted instruction
+ *         : r3 = saved SPSR
+ *
+ * Returns : r0 = address of abort
+ *         : r1 = FSR, bit 11 = write
+ *         : r2-r8 = corrupted
+ *         : r9 = preserved
+ *         : sp = pointer to registers
+ *
+ * Purpose : obtain information about current aborted instruction.
+ */
+        .align  5
+ENTRY(v7_early_abort)
+        /*
+         * The effect of data aborts on on the exclusive access monitor are
+         * UNPREDICTABLE. Do a CLREX to clear the state
+         */
+        clrex
+
+        mrc     p15, 0, r1, c5, c0, 0           @ get FSR
+        mrc     p15, 0, r0, c6, c0, 0           @ get FAR
+
+        /*
+         * V6 code adjusts the returned DFSR.
+         * New designs should not need to patch up faults.
+         */
+        mov     pc, lr
diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S
new file mode 100644
index 000000000000..35ffc4d95997
--- /dev/null
+++ b/arch/arm/mm/cache-v7.S
@@ -0,0 +1,253 @@
+/*
+ *  linux/arch/arm/mm/cache-v7.S
+ *
+ *  Copyright (C) 2001 Deep Blue Solutions Ltd.
+ *  Copyright (C) 2005 ARM Ltd.
+ *
+ * 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 is the "shell" of the ARMv7 processor support.
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/assembler.h>
+
+#include "proc-macros.S"
+
+/*
+ *      v7_flush_dcache_all()
+ *
+ *      Flush the whole D-cache.
+ *
+ *      Corrupted registers: r0-r5, r7, r9-r11
+ *
+ *      - mm    - mm_struct describing address space
+ */
+ENTRY(v7_flush_dcache_all)
+        mrc     p15, 1, r0, c0, c0, 1           @ read clidr
+        ands    r3, r0, #0x7000000              @ extract loc from clidr
+        mov     r3, r3, lsr #23                 @ left align loc bit field
+        beq     finished                        @ if loc is 0, then no need to clean
+        mov     r10, #0                         @ start clean at cache level 0
+loop1:
+        add     r2, r10, r10, lsr #1            @ work out 3x current cache level
+        mov     r1, r0, lsr r2                  @ extract cache type bits from clidr
+        and     r1, r1, #7                      @ mask of the bits for current cache only
+        cmp     r1, #2                          @ see what cache we have at this level
+        blt     skip                            @ skip if no cache, or just i-cache
+        mcr     p15, 2, r10, c0, c0, 0          @ select current cache level in cssr
+        isb                                     @ isb to sych the new cssr&csidr
+        mrc     p15, 1, r1, c0, c0, 0           @ read the new csidr
+        and     r2, r1, #7                      @ extract the length of the cache lines
+        add     r2, r2, #4                      @ add 4 (line length offset)
+        ldr     r4, =0x3ff
+        ands    r4, r4, r1, lsr #3              @ find maximum number on the way size
+        clz     r5, r4                          @ find bit position of way size increment
+        ldr     r7, =0x7fff
+        ands    r7, r7, r1, lsr #13             @ extract max number of the index size
+loop2:
+        mov     r9, r4                          @ create working copy of max way size
+loop3:
+        orr     r11, r10, r9, lsl r5            @ factor way and cache number into r11
+        orr     r11, r11, r7, lsl r2            @ factor index number into r11
+        mcr     p15, 0, r11, c7, c14, 2         @ clean & invalidate by set/way
+        subs    r9, r9, #1                      @ decrement the way
+        bge     loop3
+        subs    r7, r7, #1                      @ decrement the index
+        bge     loop2
+skip:
+        add     r10, r10, #2                    @ increment cache number
+        cmp     r3, r10
+        bgt     loop1
+finished:
+        mov     r10, #0                         @ swith back to cache level 0
+        mcr     p15, 2, r10, c0, c0, 0          @ select current cache level in cssr
+        isb
+        mov     pc, lr
+
+/*
+ *      v7_flush_cache_all()
+ *
+ *      Flush the entire cache system.
+ *  The data cache flush is now achieved using atomic clean / invalidates
+ *  working outwards from L1 cache. This is done using Set/Way based cache
+ *  maintainance instructions.
+ *  The instruction cache can still be invalidated back to the point of
+ *  unification in a single instruction.
+ *
+ */
+ENTRY(v7_flush_kern_cache_all)
+        stmfd   sp!, {r4-r5, r7, r9-r11, lr}
+        bl      v7_flush_dcache_all
+        mov     r0, #0
+        mcr     p15, 0, r0, c7, c5, 0           @ I+BTB cache invalidate
+        ldmfd   sp!, {r4-r5, r7, r9-r11, lr}
+        mov     pc, lr
+
+/*
+ *      v7_flush_cache_all()
+ *
+ *      Flush all TLB entries in a particular address space
+ *
+ *      - mm    - mm_struct describing address space
+ */
+ENTRY(v7_flush_user_cache_all)
+        /*FALLTHROUGH*/
+
+/*
+ *      v7_flush_cache_range(start, end, flags)
+ *
+ *      Flush a range of TLB entries in the specified address space.
+ *
+ *      - start - start address (may not be aligned)
+ *      - end   - end address (exclusive, may not be aligned)
+ *      - flags - vm_area_struct flags describing address space
+ *
+ *      It is assumed that:
+ *      - we have a VIPT cache.
+ */
+ENTRY(v7_flush_user_cache_range)
+        mov     pc, lr
+
+/*
+ *      v7_coherent_kern_range(start,end)
+ *
+ *      Ensure that the I and D caches are coherent within specified
+ *      region.  This is typically used when code has been written to
+ *      a memory region, and will be executed.
+ *
+ *      - start   - virtual start address of region
+ *      - end     - virtual end address of region
+ *
+ *      It is assumed that:
+ *      - the Icache does not read data from the write buffer
+ */
+ENTRY(v7_coherent_kern_range)
+        /* FALLTHROUGH */
+
+/*
+ *      v7_coherent_user_range(start,end)
+ *
+ *      Ensure that the I and D caches are coherent within specified
+ *      region.  This is typically used when code has been written to
+ *      a memory region, and will be executed.
+ *
+ *      - start   - virtual start address of region
+ *      - end     - virtual end address of region
+ *
+ *      It is assumed that:
+ *      - the Icache does not read data from the write buffer
+ */
+ENTRY(v7_coherent_user_range)
+        dcache_line_size r2, r3
+        sub     r3, r2, #1
+        bic     r0, r0, r3
+1:      mcr     p15, 0, r0, c7, c11, 1          @ clean D line to the point of unification
+        dsb
+        mcr     p15, 0, r0, c7, c5, 1           @ invalidate I line
+        add     r0, r0, r2
+        cmp     r0, r1
+        blo     1b
+        mov     r0, #0
+        mcr     p15, 0, r0, c7, c5, 6           @ invalidate BTB
+        dsb
+        isb
+        mov     pc, lr
+
+/*
+ *      v7_flush_kern_dcache_page(kaddr)
+ *
+ *      Ensure that the data held in the page kaddr is written back
+ *      to the page in question.
+ *
+ *      - kaddr   - kernel address (guaranteed to be page aligned)
+ */
+ENTRY(v7_flush_kern_dcache_page)
+        dcache_line_size r2, r3
+        add     r1, r0, #PAGE_SZ
+1:
+        mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D line / unified line
+        add     r0, r0, r2
+        cmp     r0, r1
+        blo     1b
+        dsb
+        mov     pc, lr
+
+/*
+ *      v7_dma_inv_range(start,end)
+ *
+ *      Invalidate the data cache within the specified region; we will
+ *      be performing a DMA operation in this region and we want to
+ *      purge old data in the cache.
+ *
+ *      - start   - virtual start address of region
+ *      - end     - virtual end address of region
+ */
+ENTRY(v7_dma_inv_range)
+        dcache_line_size r2, r3
+        sub     r3, r2, #1
+        tst     r0, r3
+        bic     r0, r0, r3
+        mcrne   p15, 0, r0, c7, c14, 1          @ clean & invalidate D / U line
+
+        tst     r1, r3
+        bic     r1, r1, r3
+        mcrne   p15, 0, r1, c7, c14, 1          @ clean & invalidate D / U line
+1:
+        mcr     p15, 0, r0, c7, c6, 1           @ invalidate D / U line
+        add     r0, r0, r2
+        cmp     r0, r1
+        blo     1b
+        dsb
+        mov     pc, lr
+
+/*
+ *      v7_dma_clean_range(start,end)
+ *      - start   - virtual start address of region
+ *      - end     - virtual end address of region
+ */
+ENTRY(v7_dma_clean_range)
+        dcache_line_size r2, r3
+        sub     r3, r2, #1
+        bic     r0, r0, r3
+1:
+        mcr     p15, 0, r0, c7, c10, 1          @ clean D / U line
+        add     r0, r0, r2
+        cmp     r0, r1
+        blo     1b
+        dsb
+        mov     pc, lr
+
+/*
+ *      v7_dma_flush_range(start,end)
+ *      - start   - virtual start address of region
+ *      - end     - virtual end address of region
+ */
+ENTRY(v7_dma_flush_range)
+        dcache_line_size r2, r3
+        sub     r3, r2, #1
+        bic     r0, r0, r3
+1:
+        mcr     p15, 0, r0, c7, c14, 1          @ clean & invalidate D / U line
+        add     r0, r0, r2
+        cmp     r0, r1
+        blo     1b
+        dsb
+        mov     pc, lr
+
+        __INITDATA
+
+        .type   v7_cache_fns, #object
+ENTRY(v7_cache_fns)
+        .long   v7_flush_kern_cache_all
+        .long   v7_flush_user_cache_all
+        .long   v7_flush_user_cache_range
+        .long   v7_coherent_kern_range
+        .long   v7_coherent_user_range
+        .long   v7_flush_kern_dcache_page
+        .long   v7_dma_inv_range
+        .long   v7_dma_clean_range
+        .long   v7_dma_flush_range
+        .size   v7_cache_fns, . - v7_cache_fns
diff --git a/arch/arm/mm/proc-macros.S b/arch/arm/mm/proc-macros.S
index 9e2c89eb2115..b13150052a76 100644
--- a/arch/arm/mm/proc-macros.S
+++ b/arch/arm/mm/proc-macros.S
@@ -59,3 +59,15 @@
         .word   \ucset
 #endif
         .endm
+
+/*
+ * cache_line_size - get the cache line size from the CSIDR register
+ * (available on ARMv7+). It assumes that the CSSR register was configured
+ * to access the L1 data cache CSIDR.
+ */
+        .macro  dcache_line_size, reg, tmp
+        mrc     p15, 1, \tmp, c0, c0, 0         @ read CSIDR
+        and     \tmp, \tmp, #7                  @ cache line size encoding
+        mov     \reg, #16                       @ size offset
+        mov     \reg, \reg, lsl \tmp            @ actual cache line size
+        .endm
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
new file mode 100644
index 000000000000..dd823dd4a374
--- /dev/null
+++ b/arch/arm/mm/proc-v7.S
@@ -0,0 +1,262 @@
+/*
+ *  linux/arch/arm/mm/proc-v7.S
+ *
+ *  Copyright (C) 2001 Deep Blue Solutions Ltd.
+ *
+ * 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 is the "shell" of the ARMv7 processor support.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/asm-offsets.h>
+#include <asm/elf.h>
+#include <asm/pgtable-hwdef.h>
+#include <asm/pgtable.h>
+
+#include "proc-macros.S"
+
+#define TTB_C           (1 << 0)
+#define TTB_S           (1 << 1)
+#define TTB_RGN_OC_WT   (2 << 3)
+#define TTB_RGN_OC_WB   (3 << 3)
+
+ENTRY(cpu_v7_proc_init)
+        mov     pc, lr
+
+ENTRY(cpu_v7_proc_fin)
+        mov     pc, lr
+
+/*
+ *      cpu_v7_reset(loc)
+ *
+ *      Perform a soft reset of the system.  Put the CPU into the
+ *      same state as it would be if it had been reset, and branch
+ *      to what would be the reset vector.
+ *
+ *      - loc   - location to jump to for soft reset
+ *
+ *      It is assumed that:
+ */
+        .align  5
+ENTRY(cpu_v7_reset)
+        mov     pc, r0
+
+/*
+ *      cpu_v7_do_idle()
+ *
+ *      Idle the processor (eg, wait for interrupt).
+ *
+ *      IRQs are already disabled.
+ */
+ENTRY(cpu_v7_do_idle)
+        .long   0xe320f003                      @ ARM V7 WFI instruction
+        mov     pc, lr
+
+ENTRY(cpu_v7_dcache_clean_area)
+#ifndef TLB_CAN_READ_FROM_L1_CACHE
+        dcache_line_size r2, r3
+1:      mcr     p15, 0, r0, c7, c10, 1          @ clean D entry
+        add     r0, r0, r2
+        subs    r1, r1, r2
+        bhi     1b
+        dsb
+#endif
+        mov     pc, lr
+
+/*
+ *      cpu_v7_switch_mm(pgd_phys, tsk)
+ *
+ *      Set the translation table base pointer to be pgd_phys
+ *
+ *      - pgd_phys - physical address of new TTB
+ *
+ *      It is assumed that:
+ *      - we are not using split page tables
+ */
+ENTRY(cpu_v7_switch_mm)
+        mov     r2, #0
+        ldr     r1, [r1, #MM_CONTEXT_ID]        @ get mm->context.id
+        orr     r0, r0, #TTB_RGN_OC_WB          @ mark PTWs outer cacheable, WB
+        mcr     p15, 0, r2, c13, c0, 1          @ set reserved context ID
+        isb
+1:      mcr     p15, 0, r0, c2, c0, 0           @ set TTB 0
+        isb
+        mcr     p15, 0, r1, c13, c0, 1          @ set context ID
+        isb
+        mov     pc, lr
+
+/*
+ *      cpu_v7_set_pte_ext(ptep, pte)
+ *
+ *      Set a level 2 translation table entry.
+ *
+ *      - ptep  - pointer to level 2 translation table entry
+ *                (hardware version is stored at -1024 bytes)
+ *      - pte   - PTE value to store
+ *      - ext   - value for extended PTE bits
+ *
+ *      Permissions:
+ *        YUWD  APX AP1 AP0     SVC     User
+ *        0xxx   0   0   0      no acc  no acc
+ *        100x   1   0   1      r/o     no acc
+ *        10x0   1   0   1      r/o     no acc
+ *        1011   0   0   1      r/w     no acc
+ *        110x   0   1   0      r/w     r/o
+ *        11x0   0   1   0      r/w     r/o
+ *        1111   0   1   1      r/w     r/w
+ */
+ENTRY(cpu_v7_set_pte_ext)
+        str     r1, [r0], #-2048                @ linux version
+
+        bic     r3, r1, #0x000003f0
+        bic     r3, r3, #0x00000003
+        orr     r3, r3, r2
+        orr     r3, r3, #PTE_EXT_AP0 | 2
+
+        tst     r1, #L_PTE_WRITE
+        tstne   r1, #L_PTE_DIRTY
+        orreq   r3, r3, #PTE_EXT_APX
+
+        tst     r1, #L_PTE_USER
+        orrne   r3, r3, #PTE_EXT_AP1
+        tstne   r3, #PTE_EXT_APX
+        bicne   r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
+
+        tst     r1, #L_PTE_YOUNG
+        biceq   r3, r3, #PTE_EXT_APX | PTE_EXT_AP_MASK
+
+        tst     r1, #L_PTE_EXEC
+        orreq   r3, r3, #PTE_EXT_XN
+
+        tst     r1, #L_PTE_PRESENT
+        moveq   r3, #0
+
+        str     r3, [r0]
+        mcr     p15, 0, r0, c7, c10, 1          @ flush_pte
+        mov     pc, lr
+
+cpu_v7_name:
+        .ascii  "ARMv7 Processor"
+        .align
+
+        .section ".text.init", #alloc, #execinstr
+
+/*
+ *      __v7_setup
+ *
+ *      Initialise TLB, Caches, and MMU state ready to switch the MMU
+ *      on.  Return in r0 the new CP15 C1 control register setting.
+ *
+ *      We automatically detect if we have a Harvard cache, and use the
+ *      Harvard cache control instructions insead of the unified cache
+ *      control instructions.
+ *
+ *      This should be able to cover all ARMv7 cores.
+ *
+ *      It is assumed that:
+ *      - cache type register is implemented
+ */
+__v7_setup:
+        adr     r12, __v7_setup_stack           @ the local stack
+        stmia   r12, {r0-r5, r7, r9, r11, lr}
+        bl      v7_flush_dcache_all
+        ldmia   r12, {r0-r5, r7, r9, r11, lr}
+        mov     r10, #0
+#ifdef HARVARD_CACHE
+        mcr     p15, 0, r10, c7, c5, 0          @ I+BTB cache invalidate
+#endif
+        dsb
+        mcr     p15, 0, r10, c8, c7, 0          @ invalidate I + D TLBs
+        mcr     p15, 0, r10, c2, c0, 2          @ TTB control register
+        orr     r4, r4, #TTB_RGN_OC_WB          @ mark PTWs outer cacheable, WB
+        mcr     p15, 0, r4, c2, c0, 0           @ load TTB0
+        mcr     p15, 0, r4, c2, c0, 1           @ load TTB1
+        mov     r10, #0x1f                      @ domains 0, 1 = manager
+        mcr     p15, 0, r10, c3, c0, 0          @ load domain access register
+#ifndef CONFIG_CPU_L2CACHE_DISABLE
+        @ L2 cache configuration in the L2 aux control register
+        mrc     p15, 1, r10, c9, c0, 2
+        bic     r10, r10, #(1 << 16)            @ L2 outer cache
+        mcr     p15, 1, r10, c9, c0, 2
+        @ L2 cache is enabled in the aux control register
+        mrc     p15, 0, r10, c1, c0, 1
+        orr     r10, r10, #2
+        mcr     p15, 0, r10, c1, c0, 1
+#endif
+        mrc     p15, 0, r0, c1, c0, 0           @ read control register
+        ldr     r10, cr1_clear                  @ get mask for bits to clear
+        bic     r0, r0, r10                     @ clear bits them
+        ldr     r10, cr1_set                    @ get mask for bits to set
+        orr     r0, r0, r10                     @ set them
+        mov     pc, lr                          @ return to head.S:__ret
+
+        /*
+         *         V X F   I D LR
+         * .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM
+         * rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced
+         *         0 110       0011 1.00 .111 1101 < we want
+         */
+        .type   cr1_clear, #object
+        .type   cr1_set, #object
+cr1_clear:
+        .word   0x0120c302
+cr1_set:
+        .word   0x00c0387d
+
+__v7_setup_stack:
+        .space  4 * 11                          @ 11 registers
+
+        .type   v7_processor_functions, #object
+ENTRY(v7_processor_functions)
+        .word   v7_early_abort
+        .word   cpu_v7_proc_init
+        .word   cpu_v7_proc_fin
+        .word   cpu_v7_reset
+        .word   cpu_v7_do_idle
+        .word   cpu_v7_dcache_clean_area
+        .word   cpu_v7_switch_mm
+        .word   cpu_v7_set_pte_ext
+        .size   v7_processor_functions, . - v7_processor_functions
+
+        .type   cpu_arch_name, #object
+cpu_arch_name:
+        .asciz  "armv7"
+        .size   cpu_arch_name, . - cpu_arch_name
+
+        .type   cpu_elf_name, #object
+cpu_elf_name:
+        .asciz  "v7"
+        .size   cpu_elf_name, . - cpu_elf_name
+        .align
+
+        .section ".proc.info.init", #alloc, #execinstr
+
+        /*
+         * Match any ARMv7 processor core.
+         */
+        .type   __v7_proc_info, #object
+__v7_proc_info:
+        .long   0x000f0000              @ Required ID value
+        .long   0x000f0000              @ Mask for ID
+        .long   PMD_TYPE_SECT | \
+                PMD_SECT_BUFFERABLE | \
+                PMD_SECT_CACHEABLE | \
+                PMD_SECT_AP_WRITE | \
+                PMD_SECT_AP_READ
+        .long   PMD_TYPE_SECT | \
+                PMD_SECT_XN | \
+                PMD_SECT_AP_WRITE | \
+                PMD_SECT_AP_READ
+        b       __v7_setup
+        .long   cpu_arch_name
+        .long   cpu_elf_name
+        .long   HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
+        .long   cpu_v7_name
+        .long   v7_processor_functions
+        .long   v6wbi_tlb_fns
+        .long   v6_user_fns
+        .long   v7_cache_fns
+        .size   __v7_proc_info, . - __v7_proc_info