[ARM] nommu: add ARM946E-S core support
This patch adds ARM946E-S core support which has typically 8KB I&D cache.
It has a MPU and supports ARMv5TE instruction set.
Because the ARM946E-S core can be synthesizable with various cache size,
CONFIG_CPU_DCACHE_SIZE is defined for vendor specific configurations.
Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/proc-arm946.S b/arch/arm/mm/proc-arm946.S
new file mode 100644
index 0000000..6dc7942
--- /dev/null
+++ b/arch/arm/mm/proc-arm946.S
@@ -0,0 +1,424 @@
+/*
+ * linux/arch/arm/mm/arm946.S: utility functions for ARM946E-S
+ *
+ * Copyright (C) 2004-2006 Hyok S. Choi (hyok.choi@samsung.com)
+ *
+ * (Many of cache codes are from proc-arm926.S)
+ *
+ * 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.
+ *
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/assembler.h>
+#include <asm/pgtable-hwdef.h>
+#include <asm/pgtable.h>
+#include <asm/procinfo.h>
+#include <asm/ptrace.h>
+
+/*
+ * ARM946E-S is synthesizable to have 0KB to 1MB sized D-Cache,
+ * comprising 256 lines of 32 bytes (8 words).
+ */
+#define CACHE_DSIZE (CONFIG_CPU_DCACHE_SIZE) /* typically 8KB. */
+#define CACHE_DLINESIZE 32 /* fixed */
+#define CACHE_DSEGMENTS 4 /* fixed */
+#define CACHE_DENTRIES (CACHE_DSIZE / CACHE_DSEGMENTS / CACHE_DLINESIZE)
+#define CACHE_DLIMIT (CACHE_DSIZE * 4) /* benchmark needed */
+
+ .text
+/*
+ * cpu_arm946_proc_init()
+ * cpu_arm946_switch_mm()
+ *
+ * These are not required.
+ */
+ENTRY(cpu_arm946_proc_init)
+ENTRY(cpu_arm946_switch_mm)
+ mov pc, lr
+
+/*
+ * cpu_arm946_proc_fin()
+ */
+ENTRY(cpu_arm946_proc_fin)
+ stmfd sp!, {lr}
+ mov ip, #PSR_F_BIT | PSR_I_BIT | SVC_MODE
+ msr cpsr_c, ip
+ bl arm946_flush_kern_cache_all
+ mrc p15, 0, r0, c1, c0, 0 @ ctrl register
+ bic r0, r0, #0x00001000 @ i-cache
+ bic r0, r0, #0x00000004 @ d-cache
+ mcr p15, 0, r0, c1, c0, 0 @ disable caches
+ ldmfd sp!, {pc}
+
+/*
+ * cpu_arm946_reset(loc)
+ * Params : r0 = address to jump to
+ * Notes : This sets up everything for a reset
+ */
+ENTRY(cpu_arm946_reset)
+ mov ip, #0
+ mcr p15, 0, ip, c7, c5, 0 @ flush I cache
+ mcr p15, 0, ip, c7, c6, 0 @ flush D cache
+ mcr p15, 0, ip, c7, c10, 4 @ drain WB
+ mrc p15, 0, ip, c1, c0, 0 @ ctrl register
+ bic ip, ip, #0x00000005 @ .............c.p
+ bic ip, ip, #0x00001000 @ i-cache
+ mcr p15, 0, ip, c1, c0, 0 @ ctrl register
+ mov pc, r0
+
+/*
+ * cpu_arm946_do_idle()
+ */
+ .align 5
+ENTRY(cpu_arm946_do_idle)
+ mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
+ mov pc, lr
+
+/*
+ * flush_user_cache_all()
+ */
+ENTRY(arm946_flush_user_cache_all)
+ /* FALLTHROUGH */
+
+/*
+ * flush_kern_cache_all()
+ *
+ * Clean and invalidate the entire cache.
+ */
+ENTRY(arm946_flush_kern_cache_all)
+ mov r2, #VM_EXEC
+ mov ip, #0
+__flush_whole_cache:
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, ip, c7, c6, 0 @ flush D cache
+#else
+ mov r1, #(CACHE_DSEGMENTS - 1) << 29 @ 4 segments
+1: orr r3, r1, #(CACHE_DENTRIES - 1) << 4 @ n entries
+2: mcr p15, 0, r3, c7, c14, 2 @ clean/flush D index
+ subs r3, r3, #1 << 4
+ bcs 2b @ entries n to 0
+ subs r1, r1, #1 << 29
+ bcs 1b @ segments 3 to 0
+#endif
+ tst r2, #VM_EXEC
+ mcrne p15, 0, ip, c7, c5, 0 @ flush I cache
+ mcrne p15, 0, ip, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/*
+ * flush_user_cache_range(start, end, flags)
+ *
+ * Clean and invalidate a range of cache entries in the
+ * specified address range.
+ *
+ * - start - start address (inclusive)
+ * - end - end address (exclusive)
+ * - flags - vm_flags describing address space
+ * (same as arm926)
+ */
+ENTRY(arm946_flush_user_cache_range)
+ mov ip, #0
+ sub r3, r1, r0 @ calculate total size
+ cmp r3, #CACHE_DLIMIT
+ bhs __flush_whole_cache
+
+1: tst r2, #VM_EXEC
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+ mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+#else
+ mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+ mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+#endif
+ cmp r0, r1
+ blo 1b
+ tst r2, #VM_EXEC
+ mcrne p15, 0, ip, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/*
+ * coherent_kern_range(start, end)
+ *
+ * Ensure coherency between the Icache and the Dcache in the
+ * region described by start, end. If you have non-snooping
+ * Harvard caches, you need to implement this function.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ */
+ENTRY(arm946_coherent_kern_range)
+ /* FALLTHROUGH */
+
+/*
+ * coherent_user_range(start, end)
+ *
+ * Ensure coherency between the Icache and the Dcache in the
+ * region described by start, end. If you have non-snooping
+ * Harvard caches, you need to implement this function.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ * (same as arm926)
+ */
+ENTRY(arm946_coherent_user_range)
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/*
+ * flush_kern_dcache_page(void *page)
+ *
+ * Ensure no D cache aliasing occurs, either with itself or
+ * the I cache
+ *
+ * - addr - page aligned address
+ * (same as arm926)
+ */
+ENTRY(arm946_flush_kern_dcache_page)
+ add r1, r0, #PAGE_SZ
+1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mov r0, #0
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/*
+ * dma_inv_range(start, end)
+ *
+ * Invalidate (discard) the specified virtual address range.
+ * May not write back any entries. If 'start' or 'end'
+ * are not cache line aligned, those lines must be written
+ * back.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ * (same as arm926)
+ */
+ENTRY(arm946_dma_inv_range)
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+ tst r0, #CACHE_DLINESIZE - 1
+ mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
+ tst r1, #CACHE_DLINESIZE - 1
+ mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
+#endif
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/*
+ * dma_clean_range(start, end)
+ *
+ * Clean the specified virtual address range.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ *
+ * (same as arm926)
+ */
+ENTRY(arm946_dma_clean_range)
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+#endif
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/*
+ * dma_flush_range(start, end)
+ *
+ * Clean and invalidate the specified virtual address range.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ *
+ * (same as arm926)
+ */
+ENTRY(arm946_dma_flush_range)
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1:
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
+#else
+ mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+#endif
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+ENTRY(arm946_cache_fns)
+ .long arm946_flush_kern_cache_all
+ .long arm946_flush_user_cache_all
+ .long arm946_flush_user_cache_range
+ .long arm946_coherent_kern_range
+ .long arm946_coherent_user_range
+ .long arm946_flush_kern_dcache_page
+ .long arm946_dma_inv_range
+ .long arm946_dma_clean_range
+ .long arm946_dma_flush_range
+
+
+ENTRY(cpu_arm946_dcache_clean_area)
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ add r0, r0, #CACHE_DLINESIZE
+ subs r1, r1, #CACHE_DLINESIZE
+ bhi 1b
+#endif
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+ __INIT
+
+ .type __arm946_setup, #function
+__arm946_setup:
+ mov r0, #0
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
+ mcr p15, 0, r0, c7, c6, 0 @ invalidate D cache
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+
+ mcr p15, 0, r0, c6, c3, 0 @ disable memory region 3~7
+ mcr p15, 0, r0, c6, c4, 0
+ mcr p15, 0, r0, c6, c5, 0
+ mcr p15, 0, r0, c6, c6, 0
+ mcr p15, 0, r0, c6, c7, 0
+
+ mov r0, #0x0000003F @ base = 0, size = 4GB
+ mcr p15, 0, r0, c6, c0, 0 @ set region 0, default
+
+ ldr r0, =(CONFIG_DRAM_BASE & 0xFFFFF000) @ base[31:12] of RAM
+ ldr r1, =(CONFIG_DRAM_SIZE >> 12) @ size of RAM (must be >= 4KB)
+ mov r2, #10 @ 11 is the minimum (4KB)
+1: add r2, r2, #1 @ area size *= 2
+ mov r1, r1, lsr #1
+ bne 1b @ count not zero r-shift
+ orr r0, r0, r2, lsl #1 @ the region register value
+ orr r0, r0, #1 @ set enable bit
+ mcr p15, 0, r0, c6, c1, 0 @ set region 1, RAM
+
+ ldr r0, =(CONFIG_FLASH_MEM_BASE & 0xFFFFF000) @ base[31:12] of FLASH
+ ldr r1, =(CONFIG_FLASH_SIZE >> 12) @ size of FLASH (must be >= 4KB)
+ mov r2, #10 @ 11 is the minimum (4KB)
+1: add r2, r2, #1 @ area size *= 2
+ mov r1, r1, lsr #1
+ bne 1b @ count not zero r-shift
+ orr r0, r0, r2, lsl #1 @ the region register value
+ orr r0, r0, #1 @ set enable bit
+ mcr p15, 0, r0, c6, c2, 0 @ set region 2, ROM/FLASH
+
+ mov r0, #0x06
+ mcr p15, 0, r0, c2, c0, 0 @ region 1,2 d-cacheable
+ mcr p15, 0, r0, c2, c0, 1 @ region 1,2 i-cacheable
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mov r0, #0x00 @ disable whole write buffer
+#else
+ mov r0, #0x02 @ region 1 write bufferred
+#endif
+ mcr p15, 0, r0, c3, c0, 0
+
+/*
+ * Access Permission Settings for future permission control by PU.
+ *
+ * priv. user
+ * region 0 (whole) rw -- : b0001
+ * region 1 (RAM) rw rw : b0011
+ * region 2 (FLASH) rw r- : b0010
+ * region 3~7 (none) -- -- : b0000
+ */
+ mov r0, #0x00000031
+ orr r0, r0, #0x00000200
+ mcr p15, 0, r0, c5, c0, 2 @ set data access permission
+ mcr p15, 0, r0, c5, c0, 3 @ set inst. access permission
+
+ mrc p15, 0, r0, c1, c0 @ get control register
+ orr r0, r0, #0x00001000 @ I-cache
+ orr r0, r0, #0x00000005 @ MPU/D-cache
+#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
+ orr r0, r0, #0x00004000 @ .1.. .... .... ....
+#endif
+ mov pc, lr
+
+ .size __arm946_setup, . - __arm946_setup
+
+ __INITDATA
+
+/*
+ * Purpose : Function pointers used to access above functions - all calls
+ * come through these
+ */
+ .type arm946_processor_functions, #object
+ENTRY(arm946_processor_functions)
+ .word v5t_early_abort
+ .word cpu_arm946_proc_init
+ .word cpu_arm946_proc_fin
+ .word cpu_arm946_reset
+ .word cpu_arm946_do_idle
+
+ .word cpu_arm946_dcache_clean_area
+ .word cpu_arm946_switch_mm
+ .word 0 @ cpu_*_set_pte
+ .size arm946_processor_functions, . - arm946_processor_functions
+
+ .section ".rodata"
+
+ .type cpu_arch_name, #object
+cpu_arch_name:
+ .asciz "armv5te"
+ .size cpu_arch_name, . - cpu_arch_name
+
+ .type cpu_elf_name, #object
+cpu_elf_name:
+ .asciz "v5t"
+ .size cpu_elf_name, . - cpu_elf_name
+
+ .type cpu_arm946_name, #object
+cpu_arm946_name:
+ .ascii "ARM946E-S"
+ .size cpu_arm946_name, . - cpu_arm946_name
+
+ .align
+
+ .section ".proc.info.init", #alloc, #execinstr
+ .type __arm946_proc_info,#object
+__arm946_proc_info:
+ .long 0x41009460
+ .long 0xff00fff0
+ .long 0
+ b __arm946_setup
+ .long cpu_arch_name
+ .long cpu_elf_name
+ .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
+ .long cpu_arm946_name
+ .long arm946_processor_functions
+ .long 0
+ .long 0
+ .long arm940_cache_fns
+ .size __arm946_proc_info, . - __arm946_proc_info
+