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Diffstat (limited to 'arch/mips/mm/pg-r4k.c')
-rw-r--r--arch/mips/mm/pg-r4k.c489
1 files changed, 489 insertions, 0 deletions
diff --git a/arch/mips/mm/pg-r4k.c b/arch/mips/mm/pg-r4k.c
new file mode 100644
index 000000000000..9f8b16541577
--- /dev/null
+++ b/arch/mips/mm/pg-r4k.c
@@ -0,0 +1,489 @@
+/*
+ * 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)
+ */
+#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/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)
+
+/*
+ * 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 __initdata = 512;
+static int pref_offset_copy __initdata = 256;
+
+static unsigned int pref_src_mode __initdata;
+static unsigned int pref_dst_mode __initdata;
+
+static int load_offset __initdata;
+static int store_offset __initdata;
+
+static unsigned int __initdata *dest, *epc;
+
+static unsigned int instruction_pending;
+static union mips_instruction delayed_mi;
+
+static void __init 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))) {
+ 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))) {
+ 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 && ((read_c0_prid() & 0xfff0) == 0x2010)) {
+ build_nop();
+ build_nop();
+ build_nop();
+ build_nop();
+ }
+
+ if (R4600_V2_HIT_CACHEOP_WAR && ((read_c0_prid() & 0xfff0) == 0x2020))
+ 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 __init __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)
+{
+ if (cpu_has_prefetch)
+ if (reg)
+ build_dst_pref(pref_offset_copy);
+ else
+ build_dst_pref(pref_offset_clear);
+ 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_a2_a0(unsigned long offset)
+{
+ union mips_instruction mi;
+
+ BUG_ON(offset > 0x7fff);
+
+ mi.i_format.opcode = cpu_has_64bit_gp_regs ? daddiu_op : addiu_op;
+ mi.i_format.rs = 4; /* $a0 */
+ mi.i_format.rt = 6; /* $a2 */
+ mi.i_format.simmediate = offset;
+
+ emit_instruction(mi);
+}
+
+static inline void build_addiu_a1(unsigned long offset)
+{
+ union mips_instruction mi;
+
+ BUG_ON(offset > 0x7fff);
+
+ mi.i_format.opcode = cpu_has_64bit_gp_regs ? daddiu_op : addiu_op;
+ mi.i_format.rs = 5; /* $a1 */
+ mi.i_format.rt = 5; /* $a1 */
+ mi.i_format.simmediate = offset;
+
+ load_offset -= offset;
+
+ emit_instruction(mi);
+}
+
+static inline void build_addiu_a0(unsigned long offset)
+{
+ union mips_instruction mi;
+
+ BUG_ON(offset > 0x7fff);
+
+ mi.i_format.opcode = cpu_has_64bit_gp_regs ? daddiu_op : addiu_op;
+ mi.i_format.rs = 4; /* $a0 */
+ mi.i_format.rt = 4; /* $a0 */
+ mi.i_format.simmediate = offset;
+
+ store_offset -= offset;
+
+ emit_instruction(mi);
+}
+
+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 __init build_clear_page(void)
+{
+ unsigned int loop_start;
+
+ epc = (unsigned int *) &clear_page_array;
+ instruction_pending = 0;
+ store_offset = 0;
+
+ if (cpu_has_prefetch) {
+ switch (current_cpu_data.cputype) {
+ 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:
+ pref_src_mode = Pref_LoadStreamed;
+ pref_dst_mode = Pref_StoreStreamed;
+ break;
+
+ default:
+ pref_src_mode = Pref_LoadStreamed;
+ pref_dst_mode = Pref_PrepareForStore;
+ break;
+ }
+ }
+
+ build_addiu_a2_a0(PAGE_SIZE - (cpu_has_prefetch ? pref_offset_clear : 0));
+
+ if (R4600_V2_HIT_CACHEOP_WAR && ((read_c0_prid() & 0xfff0) == 0x2020))
+ 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();
+
+ flush_icache_range((unsigned long)&clear_page_array,
+ (unsigned long) epc);
+
+ BUG_ON(epc > clear_page_array + ARRAY_SIZE(clear_page_array));
+}
+
+void __init build_copy_page(void)
+{
+ unsigned int loop_start;
+
+ epc = (unsigned int *) &copy_page_array;
+ store_offset = load_offset = 0;
+ instruction_pending = 0;
+
+ build_addiu_a2_a0(PAGE_SIZE - (cpu_has_prefetch ? pref_offset_copy : 0));
+
+ if (R4600_V2_HIT_CACHEOP_WAR && ((read_c0_prid() & 0xfff0) == 0x2020))
+ 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();
+
+ flush_icache_range((unsigned long)&copy_page_array,
+ (unsigned long) epc);
+
+ BUG_ON(epc > copy_page_array + ARRAY_SIZE(copy_page_array));
+}