[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>

1 files changed, 262 insertions, 0 deletions

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