/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2005 Embedded Alley Solutions, Inc
*/
#ifndef __ASM_MACH_KERNEL_ENTRY_INIT_H
#define __ASM_MACH_KERNEL_ENTRY_INIT_H
#include <asm/cacheops.h>
#include <asm/addrspace.h>
#define CO_CONFIGPR_VALID 0x3F1F41FF /* valid bits to write to ConfigPR */
#define HAZARD_CP0 nop; nop; nop; nop; nop; nop; nop; nop; nop; nop; nop; nop;
#define CACHE_OPC 0xBC000000 /* MIPS cache instruction opcode */
#define ICACHE_LINE_SIZE 32 /* Instruction cache line size bytes */
#define DCACHE_LINE_SIZE 32 /* Data cache line size in bytes */
#define ICACHE_SET_COUNT 256 /* Instruction cache set count */
#define DCACHE_SET_COUNT 128 /* Data cache set count */
#define ICACHE_SET_SIZE (ICACHE_SET_COUNT * ICACHE_LINE_SIZE)
#define DCACHE_SET_SIZE (DCACHE_SET_COUNT * DCACHE_LINE_SIZE)
.macro kernel_entry_setup
.set push
.set noreorder
/*
* PNX8550 entry point, when running a non compressed
* kernel. When loading a zImage, the head.S code in
* arch/mips/zboot/pnx8550 will init the caches and,
* decompress the kernel, and branch to kernel_entry.
*/
cache_begin: li t0, (1<<28)
mtc0 t0, CP0_STATUS /* cp0 usable */
HAZARD_CP0
mtc0 zero, CP0_CAUSE
HAZARD_CP0
/* Set static virtual to phys address translation and TLB disabled */
mfc0 t0, CP0_CONFIG, 7
HAZARD_CP0
and t0,~((1<<19) | (1<<20)) /* TLB/MAP cleared */
mtc0 t0, CP0_CONFIG, 7
HAZARD_CP0
/* CPU boots with kseg0 cache algo set to 0x2 -- uncached */
init_icache
nop
init_dcache
nop
cachePr4450ICReset
nop
cachePr4450DCReset
nop
/* read ConfigPR into t0 */
mfc0 t0, CP0_CONFIG, 7
HAZARD_CP0
/* enable the TLB */
or t0, (1<<19)
/* disable the ICACHE: at least 10x slower */
/* or t0, (1<<26) */
/* disable the DCACHE; CONFIG_CPU_HAS_LLSC should not be set */
/* or t0, (1<<27) */
and t0, CO_CONFIGPR_VALID
/* enable TLB. */
mtc0 t0, CP0_CONFIG, 7
HAZARD_CP0
cache_end:
/* Setup CMEM_0 to MMIO address space, 2MB */
lui t0, 0x1BE0
addi t0, t0, 0x3
mtc0 $8, $22, 4
nop
/* Setup CMEM_1, 128MB */
lui t0, 0x1000
addi t0, t0, 0xf
mtc0 $8, $22, 5
nop
/* Setup CMEM_2, 32MB */
lui t0, 0x1C00
addi t0, t0, 0xb
mtc0 $8, $22, 6
nop
/* Setup CMEM_3, 0MB */
lui t0, 0x0
addi t0, t0, 0x0
mtc0 $8, $22, 7
nop
/* Enable cache */
mfc0 t0, CP0_CONFIG
HAZARD_CP0
and t0, t0, 0xFFFFFFF8
or t0, t0, 3
mtc0 t0, CP0_CONFIG
HAZARD_CP0
.set pop
.endm
.macro init_icache
.set push
.set noreorder
/* Get Cache Configuration */
mfc0 t3, CP0_CONFIG, 1
HAZARD_CP0
/* get cache Line size */
srl t1, t3, 19 /* C0_CONFIGPR_IL_SHIFT */
andi t1, t1, 0x7 /* C0_CONFIGPR_IL_MASK */
beq t1, zero, pr4450_instr_cache_invalidated /* if zero instruction cache is absent */
nop
addiu t0, t1, 1
ori t1, zero, 1
sllv t1, t1, t0
/* get max cache Index */
srl t2, t3, 22 /* C0_CONFIGPR_IS_SHIFT */
andi t2, t2, 0x7 /* C0_CONFIGPR_IS_MASK */
addiu t0, t2, 6
ori t2, zero, 1
sllv t2, t2, t0
/* get max cache way */
srl t3, t3, 16 /* C0_CONFIGPR_IA_SHIFT */
andi t3, t3, 0x7 /* C0_CONFIGPR_IA_MASK */
addiu t3, t3, 1
/* total no of cache lines */
multu t2, t3 /* max index * max way */
mflo t2
addiu t2, t2, -1
move t0, zero
pr4450_next_instruction_cache_set:
cache Index_Invalidate_I, 0(t0)
addu t0, t0, t1 /* add bytes in a line */
bne t2, zero, pr4450_next_instruction_cache_set
addiu t2, t2, -1 /* reduce no of lines to invalidate by one */
pr4450_instr_cache_invalidated:
.set pop
.endm
.macro init_dcache
.set push
.set noreorder
move t1, zero
/* Store Tag Information */
mtc0 zero, CP0_TAGLO, 0
HAZARD_CP0
mtc0 zero, CP0_TAGHI, 0
HAZARD_CP0
/* Cache size is 16384 = 512 lines x 32 bytes per line */
or t2, zero, (128*4)-1 /* 512 lines */
/* Invalidate all lines */
2:
cache Index_Store_Tag_D, 0(t1)
addiu t2, t2, -1
bne t2, zero, 2b
addiu t1, t1, 32 /* 32 bytes in a line */
.set pop
.endm
.macro cachePr4450ICReset
.set push
.set noreorder
/* Save CP0 status reg on entry; */
/* disable interrupts during cache reset */
mfc0 t0, CP0_STATUS /* T0 = interrupt status on entry */
HAZARD_CP0
mtc0 zero, CP0_STATUS /* disable CPU interrupts */
HAZARD_CP0
or t1, zero, zero /* T1 = starting cache index (0) */
ori t2, zero, (256 - 1) /* T2 = inst cache set cnt - 1 */
icache_invd_loop:
/* 9 == register t1 */
.word (CACHE_OPC | (9 << 21) | (Index_Invalidate_I << 16) | \
(0 * ICACHE_SET_SIZE)) /* invalidate inst cache WAY0 */
.word (CACHE_OPC | (9 << 21) | (Index_Invalidate_I << 16) | \
(1 * ICACHE_SET_SIZE)) /* invalidate inst cache WAY1 */
addiu t1, t1, ICACHE_LINE_SIZE /* T1 = next cache line index */
bne t2, zero, icache_invd_loop /* T2 = 0 if all sets invalidated */
addiu t2, t2, -1 /* decrement T2 set cnt (delay slot) */
/* Initialize the latches in the instruction cache tag */
/* that drive the way selection tri-state bus drivers, by doing a */
/* dummy load while the instruction cache is still disabled. */
/* TODO: Is this needed ? */
la t1, KSEG0 /* T1 = cached memory base address */
lw zero, 0x0000(t1) /* (dummy read of first memory word) */
mtc0 t0, CP0_STATUS /* restore interrupt status on entry */
HAZARD_CP0
.set pop
.endm
.macro cachePr4450DCReset
.set push
.set noreorder
mfc0 t0, CP0_STATUS /* T0 = interrupt status on entry */
HAZARD_CP0
mtc0 zero, CP0_STATUS /* disable CPU interrupts */
HAZARD_CP0
/* Writeback/invalidate entire data cache sets/ways/lines */
or t1, zero, zero /* T1 = starting cache index (0) */
ori t2, zero, (DCACHE_SET_COUNT - 1) /* T2 = data cache set cnt - 1 */
dcache_wbinvd_loop:
/* 9 == register t1 */
.word (CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
(0 * DCACHE_SET_SIZE)) /* writeback/invalidate WAY0 */
.word (CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
(1 * DCACHE_SET_SIZE)) /* writeback/invalidate WAY1 */
.word (CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
(2 * DCACHE_SET_SIZE)) /* writeback/invalidate WAY2 */
.word (CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
(3 * DCACHE_SET_SIZE)) /* writeback/invalidate WAY3 */
addiu t1, t1, DCACHE_LINE_SIZE /* T1 = next data cache line index */
bne t2, zero, dcache_wbinvd_loop /* T2 = 0 when wbinvd entire cache */
addiu t2, t2, -1 /* decrement T2 set cnt (delay slot) */
/* Initialize the latches in the data cache tag that drive the way
selection tri-state bus drivers, by doing a dummy load while the
data cache is still in the disabled mode. TODO: Is this needed ? */
la t1, KSEG0 /* T1 = cached memory base address */
lw zero, 0x0000(t1) /* (dummy read of first memory word) */
mtc0 t0, CP0_STATUS /* restore interrupt status on entry */
HAZARD_CP0
.set pop
.endm
#endif /* __ASM_MACH_KERNEL_ENTRY_INIT_H */
