diff options
author | Thiemo Seufer <ths@networkno.de> | 2008-02-18 19:32:49 +0000 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2008-04-28 17:14:23 +0100 |
commit | fb2a27e743cd565c25cd896911e494482a8b7251 (patch) | |
tree | 791190ead6211e829443185fb1d4b4109fbd9a34 /arch/mips/mm/pg-r4k.c | |
parent | 064922a805ec7aadfafdd27aa6b4908d737c3c1d (diff) |
[MIPS] Reimplement clear_page/copy_page
Fold the SB-1 specific implementation of clear_page/copy_page in the
generic version, and rewrite that one in tlbex style. The immediate
benefits:
- It converts the compile-time workaround for SB-1 pass 1 prefetches
to a more efficient run-time check.
- It allows adjustment of loop unfolling, which helps to reduce the
number of redundant cdex cache ops.
- It fixes some esoteric cornercases (the cache line length calculations
can go wrong, and support for 64k pages without prefetch instructions
will overflow the addiu immediate).
- Somewhat better guesses of "good" prefetch values.
Signed-off-by: Thiemo Seufer <ths@networkno.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/mm/pg-r4k.c')
-rw-r--r-- | arch/mips/mm/pg-r4k.c | 534 |
1 files changed, 0 insertions, 534 deletions
diff --git a/arch/mips/mm/pg-r4k.c b/arch/mips/mm/pg-r4k.c deleted file mode 100644 index 455dedb5b39..00000000000 --- a/arch/mips/mm/pg-r4k.c +++ /dev/null @@ -1,534 +0,0 @@ -/* - * 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) 2003, 04, 05 Ralf Baechle (ralf@linux-mips.org) - * Copyright (C) 2007 Maciej W. Rozycki - */ -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/module.h> -#include <linux/proc_fs.h> - -#include <asm/bugs.h> -#include <asm/cacheops.h> -#include <asm/inst.h> -#include <asm/io.h> -#include <asm/page.h> -#include <asm/pgtable.h> -#include <asm/prefetch.h> -#include <asm/system.h> -#include <asm/bootinfo.h> -#include <asm/mipsregs.h> -#include <asm/mmu_context.h> -#include <asm/cpu.h> -#include <asm/war.h> - -#define half_scache_line_size() (cpu_scache_line_size() >> 1) -#define cpu_is_r4600_v1_x() ((read_c0_prid() & 0xfffffff0) == 0x00002010) -#define cpu_is_r4600_v2_x() ((read_c0_prid() & 0xfffffff0) == 0x00002020) - - -/* - * Maximum sizes: - * - * R4000 128 bytes S-cache: 0x58 bytes - * R4600 v1.7: 0x5c bytes - * R4600 v2.0: 0x60 bytes - * With prefetching, 16 byte strides 0xa0 bytes - */ - -static unsigned int clear_page_array[0x130 / 4]; - -void clear_page(void * page) __attribute__((alias("clear_page_array"))); - -EXPORT_SYMBOL(clear_page); - -/* - * Maximum sizes: - * - * R4000 128 bytes S-cache: 0x11c bytes - * R4600 v1.7: 0x080 bytes - * R4600 v2.0: 0x07c bytes - * With prefetching, 16 byte strides 0x0b8 bytes - */ -static unsigned int copy_page_array[0x148 / 4]; - -void copy_page(void *to, void *from) __attribute__((alias("copy_page_array"))); - -EXPORT_SYMBOL(copy_page); - -/* - * This is suboptimal for 32-bit kernels; we assume that R10000 is only used - * with 64-bit kernels. The prefetch offsets have been experimentally tuned - * an Origin 200. - */ -static int pref_offset_clear __cpuinitdata = 512; -static int pref_offset_copy __cpuinitdata = 256; - -static unsigned int pref_src_mode __cpuinitdata; -static unsigned int pref_dst_mode __cpuinitdata; - -static int load_offset __cpuinitdata; -static int store_offset __cpuinitdata; - -static unsigned int __cpuinitdata *dest, *epc; - -static unsigned int instruction_pending; -static union mips_instruction delayed_mi; - -static void __cpuinit emit_instruction(union mips_instruction mi) -{ - if (instruction_pending) - *epc++ = delayed_mi.word; - - instruction_pending = 1; - delayed_mi = mi; -} - -static inline void flush_delay_slot_or_nop(void) -{ - if (instruction_pending) { - *epc++ = delayed_mi.word; - instruction_pending = 0; - return; - } - - *epc++ = 0; -} - -static inline unsigned int *label(void) -{ - if (instruction_pending) { - *epc++ = delayed_mi.word; - instruction_pending = 0; - } - - return epc; -} - -static inline void build_insn_word(unsigned int word) -{ - union mips_instruction mi; - - mi.word = word; - - emit_instruction(mi); -} - -static inline void build_nop(void) -{ - build_insn_word(0); /* nop */ -} - -static inline void build_src_pref(int advance) -{ - if (!(load_offset & (cpu_dcache_line_size() - 1)) && advance) { - union mips_instruction mi; - - mi.i_format.opcode = pref_op; - mi.i_format.rs = 5; /* $a1 */ - mi.i_format.rt = pref_src_mode; - mi.i_format.simmediate = load_offset + advance; - - emit_instruction(mi); - } -} - -static inline void __build_load_reg(int reg) -{ - union mips_instruction mi; - unsigned int width; - - if (cpu_has_64bit_gp_regs) { - mi.i_format.opcode = ld_op; - width = 8; - } else { - mi.i_format.opcode = lw_op; - width = 4; - } - mi.i_format.rs = 5; /* $a1 */ - mi.i_format.rt = reg; /* $reg */ - mi.i_format.simmediate = load_offset; - - load_offset += width; - emit_instruction(mi); -} - -static inline void build_load_reg(int reg) -{ - if (cpu_has_prefetch) - build_src_pref(pref_offset_copy); - - __build_load_reg(reg); -} - -static inline void build_dst_pref(int advance) -{ - if (!(store_offset & (cpu_dcache_line_size() - 1)) && advance) { - union mips_instruction mi; - - mi.i_format.opcode = pref_op; - mi.i_format.rs = 4; /* $a0 */ - mi.i_format.rt = pref_dst_mode; - mi.i_format.simmediate = store_offset + advance; - - emit_instruction(mi); - } -} - -static inline void build_cdex_s(void) -{ - union mips_instruction mi; - - if ((store_offset & (cpu_scache_line_size() - 1))) - return; - - mi.c_format.opcode = cache_op; - mi.c_format.rs = 4; /* $a0 */ - mi.c_format.c_op = 3; /* Create Dirty Exclusive */ - mi.c_format.cache = 3; /* Secondary Data Cache */ - mi.c_format.simmediate = store_offset; - - emit_instruction(mi); -} - -static inline void build_cdex_p(void) -{ - union mips_instruction mi; - - if (store_offset & (cpu_dcache_line_size() - 1)) - return; - - if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) { - build_nop(); - build_nop(); - build_nop(); - build_nop(); - } - - if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x()) - build_insn_word(0x8c200000); /* lw $zero, ($at) */ - - mi.c_format.opcode = cache_op; - mi.c_format.rs = 4; /* $a0 */ - mi.c_format.c_op = 3; /* Create Dirty Exclusive */ - mi.c_format.cache = 1; /* Data Cache */ - mi.c_format.simmediate = store_offset; - - emit_instruction(mi); -} - -static void __cpuinit __build_store_reg(int reg) -{ - union mips_instruction mi; - unsigned int width; - - if (cpu_has_64bit_gp_regs || - (cpu_has_64bit_zero_reg && reg == 0)) { - mi.i_format.opcode = sd_op; - width = 8; - } else { - mi.i_format.opcode = sw_op; - width = 4; - } - mi.i_format.rs = 4; /* $a0 */ - mi.i_format.rt = reg; /* $reg */ - mi.i_format.simmediate = store_offset; - - store_offset += width; - emit_instruction(mi); -} - -static inline void build_store_reg(int reg) -{ - int pref_off = cpu_has_prefetch ? - (reg ? pref_offset_copy : pref_offset_clear) : 0; - if (pref_off) - build_dst_pref(pref_off); - else if (cpu_has_cache_cdex_s) - build_cdex_s(); - else if (cpu_has_cache_cdex_p) - build_cdex_p(); - - __build_store_reg(reg); -} - -static inline void build_addiu_rt_rs(unsigned int rt, unsigned int rs, - unsigned long offset) -{ - union mips_instruction mi; - - BUG_ON(offset > 0x7fff); - - if (cpu_has_64bit_gp_regs && DADDI_WAR && r4k_daddiu_bug()) { - mi.i_format.opcode = addiu_op; - mi.i_format.rs = 0; /* $zero */ - mi.i_format.rt = 25; /* $t9 */ - mi.i_format.simmediate = offset; - emit_instruction(mi); - - mi.r_format.opcode = spec_op; - mi.r_format.rs = rs; - mi.r_format.rt = 25; /* $t9 */ - mi.r_format.rd = rt; - mi.r_format.re = 0; - mi.r_format.func = daddu_op; - } else { - mi.i_format.opcode = cpu_has_64bit_gp_regs ? - daddiu_op : addiu_op; - mi.i_format.rs = rs; - mi.i_format.rt = rt; - mi.i_format.simmediate = offset; - } - emit_instruction(mi); -} - -static inline void build_addiu_a2_a0(unsigned long offset) -{ - build_addiu_rt_rs(6, 4, offset); /* $a2, $a0, offset */ -} - -static inline void build_addiu_a2(unsigned long offset) -{ - build_addiu_rt_rs(6, 6, offset); /* $a2, $a2, offset */ -} - -static inline void build_addiu_a1(unsigned long offset) -{ - build_addiu_rt_rs(5, 5, offset); /* $a1, $a1, offset */ - - load_offset -= offset; -} - -static inline void build_addiu_a0(unsigned long offset) -{ - build_addiu_rt_rs(4, 4, offset); /* $a0, $a0, offset */ - - store_offset -= offset; -} - -static inline void build_bne(unsigned int *dest) -{ - union mips_instruction mi; - - mi.i_format.opcode = bne_op; - mi.i_format.rs = 6; /* $a2 */ - mi.i_format.rt = 4; /* $a0 */ - mi.i_format.simmediate = dest - epc - 1; - - *epc++ = mi.word; - flush_delay_slot_or_nop(); -} - -static inline void build_jr_ra(void) -{ - union mips_instruction mi; - - mi.r_format.opcode = spec_op; - mi.r_format.rs = 31; - mi.r_format.rt = 0; - mi.r_format.rd = 0; - mi.r_format.re = 0; - mi.r_format.func = jr_op; - - *epc++ = mi.word; - flush_delay_slot_or_nop(); -} - -void __cpuinit build_clear_page(void) -{ - unsigned int loop_start; - unsigned long off; - int i; - - epc = (unsigned int *) &clear_page_array; - instruction_pending = 0; - store_offset = 0; - - if (cpu_has_prefetch) { - switch (current_cpu_type()) { - case CPU_TX49XX: - /* TX49 supports only Pref_Load */ - pref_offset_clear = 0; - pref_offset_copy = 0; - break; - - case CPU_RM9000: - /* - * As a workaround for erratum G105 which make the - * PrepareForStore hint unusable we fall back to - * StoreRetained on the RM9000. Once it is known which - * versions of the RM9000 we'll be able to condition- - * alize this. - */ - - case CPU_R10000: - case CPU_R12000: - case CPU_R14000: - pref_src_mode = Pref_LoadStreamed; - pref_dst_mode = Pref_StoreStreamed; - break; - - default: - pref_src_mode = Pref_LoadStreamed; - pref_dst_mode = Pref_PrepareForStore; - break; - } - } - - off = PAGE_SIZE - (cpu_has_prefetch ? pref_offset_clear : 0); - if (off > 0x7fff) { - build_addiu_a2_a0(off >> 1); - build_addiu_a2(off >> 1); - } else - build_addiu_a2_a0(off); - - if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x()) - build_insn_word(0x3c01a000); /* lui $at, 0xa000 */ - -dest = label(); - do { - build_store_reg(0); - build_store_reg(0); - build_store_reg(0); - build_store_reg(0); - } while (store_offset < half_scache_line_size()); - build_addiu_a0(2 * store_offset); - loop_start = store_offset; - do { - build_store_reg(0); - build_store_reg(0); - build_store_reg(0); - build_store_reg(0); - } while ((store_offset - loop_start) < half_scache_line_size()); - build_bne(dest); - - if (cpu_has_prefetch && pref_offset_clear) { - build_addiu_a2_a0(pref_offset_clear); - dest = label(); - loop_start = store_offset; - do { - __build_store_reg(0); - __build_store_reg(0); - __build_store_reg(0); - __build_store_reg(0); - } while ((store_offset - loop_start) < half_scache_line_size()); - build_addiu_a0(2 * store_offset); - loop_start = store_offset; - do { - __build_store_reg(0); - __build_store_reg(0); - __build_store_reg(0); - __build_store_reg(0); - } while ((store_offset - loop_start) < half_scache_line_size()); - build_bne(dest); - } - - build_jr_ra(); - - BUG_ON(epc > clear_page_array + ARRAY_SIZE(clear_page_array)); - - pr_info("Synthesized clear page handler (%u instructions).\n", - (unsigned int)(epc - clear_page_array)); - - pr_debug("\t.set push\n"); - pr_debug("\t.set noreorder\n"); - for (i = 0; i < (epc - clear_page_array); i++) - pr_debug("\t.word 0x%08x\n", clear_page_array[i]); - pr_debug("\t.set pop\n"); -} - -void __cpuinit build_copy_page(void) -{ - unsigned int loop_start; - unsigned long off; - int i; - - epc = (unsigned int *) ©_page_array; - store_offset = load_offset = 0; - instruction_pending = 0; - - off = PAGE_SIZE - (cpu_has_prefetch ? pref_offset_copy : 0); - if (off > 0x7fff) { - build_addiu_a2_a0(off >> 1); - build_addiu_a2(off >> 1); - } else - build_addiu_a2_a0(off); - - if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x()) - build_insn_word(0x3c01a000); /* lui $at, 0xa000 */ - -dest = label(); - loop_start = store_offset; - do { - build_load_reg( 8); - build_load_reg( 9); - build_load_reg(10); - build_load_reg(11); - build_store_reg( 8); - build_store_reg( 9); - build_store_reg(10); - build_store_reg(11); - } while ((store_offset - loop_start) < half_scache_line_size()); - build_addiu_a0(2 * store_offset); - build_addiu_a1(2 * load_offset); - loop_start = store_offset; - do { - build_load_reg( 8); - build_load_reg( 9); - build_load_reg(10); - build_load_reg(11); - build_store_reg( 8); - build_store_reg( 9); - build_store_reg(10); - build_store_reg(11); - } while ((store_offset - loop_start) < half_scache_line_size()); - build_bne(dest); - - if (cpu_has_prefetch && pref_offset_copy) { - build_addiu_a2_a0(pref_offset_copy); - dest = label(); - loop_start = store_offset; - do { - __build_load_reg( 8); - __build_load_reg( 9); - __build_load_reg(10); - __build_load_reg(11); - __build_store_reg( 8); - __build_store_reg( 9); - __build_store_reg(10); - __build_store_reg(11); - } while ((store_offset - loop_start) < half_scache_line_size()); - build_addiu_a0(2 * store_offset); - build_addiu_a1(2 * load_offset); - loop_start = store_offset; - do { - __build_load_reg( 8); - __build_load_reg( 9); - __build_load_reg(10); - __build_load_reg(11); - __build_store_reg( 8); - __build_store_reg( 9); - __build_store_reg(10); - __build_store_reg(11); - } while ((store_offset - loop_start) < half_scache_line_size()); - build_bne(dest); - } - - build_jr_ra(); - - BUG_ON(epc > copy_page_array + ARRAY_SIZE(copy_page_array)); - - pr_info("Synthesized copy page handler (%u instructions).\n", - (unsigned int)(epc - copy_page_array)); - - pr_debug("\t.set push\n"); - pr_debug("\t.set noreorder\n"); - for (i = 0; i < (epc - copy_page_array); i++) - pr_debug("\t.word 0x%08x\n", copy_page_array[i]); - pr_debug("\t.set pop\n"); -} |