From fb2a27e743cd565c25cd896911e494482a8b7251 Mon Sep 17 00:00:00 2001 From: Thiemo Seufer Date: Mon, 18 Feb 2008 19:32:49 +0000 Subject: [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 Signed-off-by: Ralf Baechle --- arch/mips/mm/page.c | 684 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 684 insertions(+) create mode 100644 arch/mips/mm/page.c (limited to 'arch/mips/mm/page.c') diff --git a/arch/mips/mm/page.c b/arch/mips/mm/page.c new file mode 100644 index 00000000000..d827d614436 --- /dev/null +++ b/arch/mips/mm/page.c @@ -0,0 +1,684 @@ +/* + * 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 + * Copyright (C) 2008 Thiemo Seufer + */ +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_SIBYTE_DMA_PAGEOPS +#include +#include +#include +#endif + +#include "uasm.h" + +/* Registers used in the assembled routines. */ +#define ZERO 0 +#define AT 2 +#define A0 4 +#define A1 5 +#define A2 6 +#define T0 8 +#define T1 9 +#define T2 10 +#define T3 11 +#define T9 25 +#define RA 31 + +/* Handle labels (which must be positive integers). */ +enum label_id { + label_clear_nopref = 1, + label_clear_pref, + label_copy_nopref, + label_copy_pref_both, + label_copy_pref_store, +}; + +UASM_L_LA(_clear_nopref) +UASM_L_LA(_clear_pref) +UASM_L_LA(_copy_nopref) +UASM_L_LA(_copy_pref_both) +UASM_L_LA(_copy_pref_store) + +/* We need one branch and therefore one relocation per target label. */ +static struct uasm_label __cpuinitdata labels[5]; +static struct uasm_reloc __cpuinitdata relocs[5]; + +#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: 0x058 bytes + * R4600 v1.7: 0x05c bytes + * R4600 v2.0: 0x060 bytes + * With prefetching, 16 word strides 0x120 bytes + */ + +static u32 clear_page_array[0x120 / 4]; + +#ifdef CONFIG_SIBYTE_DMA_PAGEOPS +void clear_page_cpu(void *page) __attribute__((alias("clear_page_array"))); +#else +void clear_page(void *page) __attribute__((alias("clear_page_array"))); +#endif + +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 word strides 0x540 bytes + */ +static u32 copy_page_array[0x540 / 4]; + +#ifdef CONFIG_SIBYTE_DMA_PAGEOPS +void +copy_page_cpu(void *to, void *from) __attribute__((alias("copy_page_array"))); +#else +void copy_page(void *to, void *from) __attribute__((alias("copy_page_array"))); +#endif + +EXPORT_SYMBOL(copy_page); + + +static int pref_bias_clear_store __cpuinitdata; +static int pref_bias_copy_load __cpuinitdata; +static int pref_bias_copy_store __cpuinitdata; + +static u32 pref_src_mode __cpuinitdata; +static u32 pref_dst_mode __cpuinitdata; + +static int clear_word_size __cpuinitdata; +static int copy_word_size __cpuinitdata; + +static int half_clear_loop_size __cpuinitdata; +static int half_copy_loop_size __cpuinitdata; + +static int cache_line_size __cpuinitdata; +#define cache_line_mask() (cache_line_size - 1) + +static inline void __cpuinit +pg_addiu(u32 **buf, unsigned int reg1, unsigned int reg2, unsigned int off) +{ + if (cpu_has_64bit_gp_regs && DADDI_WAR && r4k_daddiu_bug()) { + if (off > 0x7fff) { + uasm_i_lui(buf, T9, uasm_rel_hi(off)); + uasm_i_addiu(buf, T9, T9, uasm_rel_lo(off)); + } else + uasm_i_addiu(buf, T9, ZERO, off); + uasm_i_daddu(buf, reg1, reg2, T9); + } else { + if (off > 0x7fff) { + uasm_i_lui(buf, T9, uasm_rel_hi(off)); + uasm_i_addiu(buf, T9, T9, uasm_rel_lo(off)); + UASM_i_ADDU(buf, reg1, reg2, T9); + } else + UASM_i_ADDIU(buf, reg1, reg2, off); + } +} + +static void __cpuinit set_prefetch_parameters(void) +{ + if (cpu_has_64bit_gp_regs || cpu_has_64bit_zero_reg) + clear_word_size = 8; + else + clear_word_size = 4; + + if (cpu_has_64bit_gp_regs) + copy_word_size = 8; + else + copy_word_size = 4; + + /* + * The pref's used here are using "streaming" hints, which cause the + * copied data to be kicked out of the cache sooner. A page copy often + * ends up copying a lot more data than is commonly used, so this seems + * to make sense in terms of reducing cache pollution, but I've no real + * performance data to back this up. + */ + if (cpu_has_prefetch) { + /* + * XXX: Most prefetch bias values in here are based on + * guesswork. + */ + cache_line_size = cpu_dcache_line_size(); + switch (current_cpu_type()) { + case CPU_TX49XX: + /* TX49 supports only Pref_Load */ + pref_bias_copy_load = 256; + 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: + /* + * Those values have been experimentally tuned for an + * Origin 200. + */ + pref_bias_clear_store = 512; + pref_bias_copy_load = 256; + pref_bias_copy_store = 256; + pref_src_mode = Pref_LoadStreamed; + pref_dst_mode = Pref_StoreStreamed; + break; + + case CPU_SB1: + case CPU_SB1A: + pref_bias_clear_store = 128; + pref_bias_copy_load = 128; + pref_bias_copy_store = 128; + /* + * SB1 pass1 Pref_LoadStreamed/Pref_StoreStreamed + * hints are broken. + */ + if (current_cpu_type() == CPU_SB1 && + (current_cpu_data.processor_id & 0xff) < 0x02) { + pref_src_mode = Pref_Load; + pref_dst_mode = Pref_Store; + } else { + pref_src_mode = Pref_LoadStreamed; + pref_dst_mode = Pref_StoreStreamed; + } + break; + + default: + pref_bias_clear_store = 128; + pref_bias_copy_load = 256; + pref_bias_copy_store = 128; + pref_src_mode = Pref_LoadStreamed; + pref_dst_mode = Pref_PrepareForStore; + break; + } + } else { + if (cpu_has_cache_cdex_s) + cache_line_size = cpu_scache_line_size(); + else if (cpu_has_cache_cdex_p) + cache_line_size = cpu_dcache_line_size(); + } + /* + * Too much unrolling will overflow the available space in + * clear_space_array / copy_page_array. 8 words sounds generous, + * but a R4000 with 128 byte L2 line length can exceed even that. + */ + half_clear_loop_size = min(8 * clear_word_size, + max(cache_line_size >> 1, + 4 * clear_word_size)); + half_copy_loop_size = min(8 * copy_word_size, + max(cache_line_size >> 1, + 4 * copy_word_size)); +} + +static void __cpuinit build_clear_store(u32 **buf, int off) +{ + if (cpu_has_64bit_gp_regs || cpu_has_64bit_zero_reg) { + uasm_i_sd(buf, ZERO, off, A0); + } else { + uasm_i_sw(buf, ZERO, off, A0); + } +} + +static inline void __cpuinit build_clear_pref(u32 **buf, int off) +{ + if (off & cache_line_mask()) + return; + + if (pref_bias_clear_store) { + uasm_i_pref(buf, pref_dst_mode, pref_bias_clear_store + off, + A0); + } else if (cpu_has_cache_cdex_s) { + uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0); + } else if (cpu_has_cache_cdex_p) { + if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) { + uasm_i_nop(buf); + uasm_i_nop(buf); + uasm_i_nop(buf); + uasm_i_nop(buf); + } + + if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x()) + uasm_i_lw(buf, ZERO, ZERO, AT); + + uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0); + } +} + +void __cpuinit build_clear_page(void) +{ + int off; + u32 *buf = (u32 *)&clear_page_array; + struct uasm_label *l = labels; + struct uasm_reloc *r = relocs; + int i; + + memset(labels, 0, sizeof(labels)); + memset(relocs, 0, sizeof(relocs)); + + set_prefetch_parameters(); + + /* + * This algorithm makes the following assumptions: + * - The prefetch bias is a multiple of 2 words. + * - The prefetch bias is less than one page. + */ + BUG_ON(pref_bias_clear_store % (2 * clear_word_size)); + BUG_ON(PAGE_SIZE < pref_bias_clear_store); + + off = PAGE_SIZE - pref_bias_clear_store; + if (off > 0xffff || !pref_bias_clear_store) + pg_addiu(&buf, A2, A0, off); + else + uasm_i_ori(&buf, A2, A0, off); + + if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x()) + uasm_i_lui(&buf, AT, 0xa000); + + off = min(8, pref_bias_clear_store / cache_line_size) * + cache_line_size; + while (off) { + build_clear_pref(&buf, -off); + off -= cache_line_size; + } + uasm_l_clear_pref(&l, buf); + do { + build_clear_pref(&buf, off); + build_clear_store(&buf, off); + off += clear_word_size; + } while (off < half_clear_loop_size); + pg_addiu(&buf, A0, A0, 2 * off); + off = -off; + do { + build_clear_pref(&buf, off); + if (off == -clear_word_size) + uasm_il_bne(&buf, &r, A0, A2, label_clear_pref); + build_clear_store(&buf, off); + off += clear_word_size; + } while (off < 0); + + if (pref_bias_clear_store) { + pg_addiu(&buf, A2, A0, pref_bias_clear_store); + uasm_l_clear_nopref(&l, buf); + off = 0; + do { + build_clear_store(&buf, off); + off += clear_word_size; + } while (off < half_clear_loop_size); + pg_addiu(&buf, A0, A0, 2 * off); + off = -off; + do { + if (off == -clear_word_size) + uasm_il_bne(&buf, &r, A0, A2, + label_clear_nopref); + build_clear_store(&buf, off); + off += clear_word_size; + } while (off < 0); + } + + uasm_i_jr(&buf, RA); + uasm_i_nop(&buf); + + BUG_ON(buf > clear_page_array + ARRAY_SIZE(clear_page_array)); + + uasm_resolve_relocs(relocs, labels); + + pr_debug("Synthesized clear page handler (%u instructions).\n", + (u32)(buf - clear_page_array)); + + pr_debug("\t.set push\n"); + pr_debug("\t.set noreorder\n"); + for (i = 0; i < (buf - clear_page_array); i++) + pr_debug("\t.word 0x%08x\n", clear_page_array[i]); + pr_debug("\t.set pop\n"); +} + +static void __cpuinit build_copy_load(u32 **buf, int reg, int off) +{ + if (cpu_has_64bit_gp_regs) { + uasm_i_ld(buf, reg, off, A1); + } else { + uasm_i_lw(buf, reg, off, A1); + } +} + +static void __cpuinit build_copy_store(u32 **buf, int reg, int off) +{ + if (cpu_has_64bit_gp_regs) { + uasm_i_sd(buf, reg, off, A0); + } else { + uasm_i_sw(buf, reg, off, A0); + } +} + +static inline void build_copy_load_pref(u32 **buf, int off) +{ + if (off & cache_line_mask()) + return; + + if (pref_bias_copy_load) + uasm_i_pref(buf, pref_src_mode, pref_bias_copy_load + off, A1); +} + +static inline void build_copy_store_pref(u32 **buf, int off) +{ + if (off & cache_line_mask()) + return; + + if (pref_bias_copy_store) { + uasm_i_pref(buf, pref_dst_mode, pref_bias_copy_store + off, + A0); + } else if (cpu_has_cache_cdex_s) { + uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0); + } else if (cpu_has_cache_cdex_p) { + if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) { + uasm_i_nop(buf); + uasm_i_nop(buf); + uasm_i_nop(buf); + uasm_i_nop(buf); + } + + if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x()) + uasm_i_lw(buf, ZERO, ZERO, AT); + + uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0); + } +} + +void __cpuinit build_copy_page(void) +{ + int off; + u32 *buf = (u32 *)©_page_array; + struct uasm_label *l = labels; + struct uasm_reloc *r = relocs; + int i; + + memset(labels, 0, sizeof(labels)); + memset(relocs, 0, sizeof(relocs)); + + set_prefetch_parameters(); + + /* + * This algorithm makes the following assumptions: + * - All prefetch biases are multiples of 8 words. + * - The prefetch biases are less than one page. + * - The store prefetch bias isn't greater than the load + * prefetch bias. + */ + BUG_ON(pref_bias_copy_load % (8 * copy_word_size)); + BUG_ON(pref_bias_copy_store % (8 * copy_word_size)); + BUG_ON(PAGE_SIZE < pref_bias_copy_load); + BUG_ON(pref_bias_copy_store > pref_bias_copy_load); + + off = PAGE_SIZE - pref_bias_copy_load; + if (off > 0xffff || !pref_bias_copy_load) + pg_addiu(&buf, A2, A0, off); + else + uasm_i_ori(&buf, A2, A0, off); + + if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x()) + uasm_i_lui(&buf, AT, 0xa000); + + off = min(8, pref_bias_copy_load / cache_line_size) * cache_line_size; + while (off) { + build_copy_load_pref(&buf, -off); + off -= cache_line_size; + } + off = min(8, pref_bias_copy_store / cache_line_size) * cache_line_size; + while (off) { + build_copy_store_pref(&buf, -off); + off -= cache_line_size; + } + uasm_l_copy_pref_both(&l, buf); + do { + build_copy_load_pref(&buf, off); + build_copy_load(&buf, T0, off); + build_copy_load_pref(&buf, off + copy_word_size); + build_copy_load(&buf, T1, off + copy_word_size); + build_copy_load_pref(&buf, off + 2 * copy_word_size); + build_copy_load(&buf, T2, off + 2 * copy_word_size); + build_copy_load_pref(&buf, off + 3 * copy_word_size); + build_copy_load(&buf, T3, off + 3 * copy_word_size); + build_copy_store_pref(&buf, off); + build_copy_store(&buf, T0, off); + build_copy_store_pref(&buf, off + copy_word_size); + build_copy_store(&buf, T1, off + copy_word_size); + build_copy_store_pref(&buf, off + 2 * copy_word_size); + build_copy_store(&buf, T2, off + 2 * copy_word_size); + build_copy_store_pref(&buf, off + 3 * copy_word_size); + build_copy_store(&buf, T3, off + 3 * copy_word_size); + off += 4 * copy_word_size; + } while (off < half_copy_loop_size); + pg_addiu(&buf, A1, A1, 2 * off); + pg_addiu(&buf, A0, A0, 2 * off); + off = -off; + do { + build_copy_load_pref(&buf, off); + build_copy_load(&buf, T0, off); + build_copy_load_pref(&buf, off + copy_word_size); + build_copy_load(&buf, T1, off + copy_word_size); + build_copy_load_pref(&buf, off + 2 * copy_word_size); + build_copy_load(&buf, T2, off + 2 * copy_word_size); + build_copy_load_pref(&buf, off + 3 * copy_word_size); + build_copy_load(&buf, T3, off + 3 * copy_word_size); + build_copy_store_pref(&buf, off); + build_copy_store(&buf, T0, off); + build_copy_store_pref(&buf, off + copy_word_size); + build_copy_store(&buf, T1, off + copy_word_size); + build_copy_store_pref(&buf, off + 2 * copy_word_size); + build_copy_store(&buf, T2, off + 2 * copy_word_size); + build_copy_store_pref(&buf, off + 3 * copy_word_size); + if (off == -(4 * copy_word_size)) + uasm_il_bne(&buf, &r, A2, A0, label_copy_pref_both); + build_copy_store(&buf, T3, off + 3 * copy_word_size); + off += 4 * copy_word_size; + } while (off < 0); + + if (pref_bias_copy_load - pref_bias_copy_store) { + pg_addiu(&buf, A2, A0, + pref_bias_copy_load - pref_bias_copy_store); + uasm_l_copy_pref_store(&l, buf); + off = 0; + do { + build_copy_load(&buf, T0, off); + build_copy_load(&buf, T1, off + copy_word_size); + build_copy_load(&buf, T2, off + 2 * copy_word_size); + build_copy_load(&buf, T3, off + 3 * copy_word_size); + build_copy_store_pref(&buf, off); + build_copy_store(&buf, T0, off); + build_copy_store_pref(&buf, off + copy_word_size); + build_copy_store(&buf, T1, off + copy_word_size); + build_copy_store_pref(&buf, off + 2 * copy_word_size); + build_copy_store(&buf, T2, off + 2 * copy_word_size); + build_copy_store_pref(&buf, off + 3 * copy_word_size); + build_copy_store(&buf, T3, off + 3 * copy_word_size); + off += 4 * copy_word_size; + } while (off < half_copy_loop_size); + pg_addiu(&buf, A1, A1, 2 * off); + pg_addiu(&buf, A0, A0, 2 * off); + off = -off; + do { + build_copy_load(&buf, T0, off); + build_copy_load(&buf, T1, off + copy_word_size); + build_copy_load(&buf, T2, off + 2 * copy_word_size); + build_copy_load(&buf, T3, off + 3 * copy_word_size); + build_copy_store_pref(&buf, off); + build_copy_store(&buf, T0, off); + build_copy_store_pref(&buf, off + copy_word_size); + build_copy_store(&buf, T1, off + copy_word_size); + build_copy_store_pref(&buf, off + 2 * copy_word_size); + build_copy_store(&buf, T2, off + 2 * copy_word_size); + build_copy_store_pref(&buf, off + 3 * copy_word_size); + if (off == -(4 * copy_word_size)) + uasm_il_bne(&buf, &r, A2, A0, + label_copy_pref_store); + build_copy_store(&buf, T3, off + 3 * copy_word_size); + off += 4 * copy_word_size; + } while (off < 0); + } + + if (pref_bias_copy_store) { + pg_addiu(&buf, A2, A0, pref_bias_copy_store); + uasm_l_copy_nopref(&l, buf); + off = 0; + do { + build_copy_load(&buf, T0, off); + build_copy_load(&buf, T1, off + copy_word_size); + build_copy_load(&buf, T2, off + 2 * copy_word_size); + build_copy_load(&buf, T3, off + 3 * copy_word_size); + build_copy_store(&buf, T0, off); + build_copy_store(&buf, T1, off + copy_word_size); + build_copy_store(&buf, T2, off + 2 * copy_word_size); + build_copy_store(&buf, T3, off + 3 * copy_word_size); + off += 4 * copy_word_size; + } while (off < half_copy_loop_size); + pg_addiu(&buf, A1, A1, 2 * off); + pg_addiu(&buf, A0, A0, 2 * off); + off = -off; + do { + build_copy_load(&buf, T0, off); + build_copy_load(&buf, T1, off + copy_word_size); + build_copy_load(&buf, T2, off + 2 * copy_word_size); + build_copy_load(&buf, T3, off + 3 * copy_word_size); + build_copy_store(&buf, T0, off); + build_copy_store(&buf, T1, off + copy_word_size); + build_copy_store(&buf, T2, off + 2 * copy_word_size); + if (off == -(4 * copy_word_size)) + uasm_il_bne(&buf, &r, A2, A0, + label_copy_nopref); + build_copy_store(&buf, T3, off + 3 * copy_word_size); + off += 4 * copy_word_size; + } while (off < 0); + } + + uasm_i_jr(&buf, RA); + uasm_i_nop(&buf); + + BUG_ON(buf > copy_page_array + ARRAY_SIZE(copy_page_array)); + + uasm_resolve_relocs(relocs, labels); + + pr_debug("Synthesized copy page handler (%u instructions).\n", + (u32)(buf - copy_page_array)); + + pr_debug("\t.set push\n"); + pr_debug("\t.set noreorder\n"); + for (i = 0; i < (buf - copy_page_array); i++) + pr_debug("\t.word 0x%08x\n", copy_page_array[i]); + pr_debug("\t.set pop\n"); +} + +#ifdef CONFIG_SIBYTE_DMA_PAGEOPS + +/* + * Pad descriptors to cacheline, since each is exclusively owned by a + * particular CPU. + */ +struct dmadscr { + u64 dscr_a; + u64 dscr_b; + u64 pad_a; + u64 pad_b; +} ____cacheline_aligned_in_smp page_descr[DM_NUM_CHANNELS]; + +void sb1_dma_init(void) +{ + int i; + + for (i = 0; i < DM_NUM_CHANNELS; i++) { + const u64 base_val = CPHYSADDR((unsigned long)&page_descr[i]) | + V_DM_DSCR_BASE_RINGSZ(1); + void *base_reg = IOADDR(A_DM_REGISTER(i, R_DM_DSCR_BASE)); + + __raw_writeq(base_val, base_reg); + __raw_writeq(base_val | M_DM_DSCR_BASE_RESET, base_reg); + __raw_writeq(base_val | M_DM_DSCR_BASE_ENABL, base_reg); + } +} + +void clear_page(void *page) +{ + u64 to_phys = CPHYSADDR((unsigned long)page); + unsigned int cpu = smp_processor_id(); + + /* if the page is not in KSEG0, use old way */ + if ((long)KSEGX((unsigned long)page) != (long)CKSEG0) + return clear_page_cpu(page); + + page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_ZERO_MEM | + M_DM_DSCRA_L2C_DEST | M_DM_DSCRA_INTERRUPT; + page_descr[cpu].dscr_b = V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE); + __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT))); + + /* + * Don't really want to do it this way, but there's no + * reliable way to delay completion detection. + */ + while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG))) + & M_DM_DSCR_BASE_INTERRUPT)) + ; + __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE))); +} + +void copy_page(void *to, void *from) +{ + u64 from_phys = CPHYSADDR((unsigned long)from); + u64 to_phys = CPHYSADDR((unsigned long)to); + unsigned int cpu = smp_processor_id(); + + /* if any page is not in KSEG0, use old way */ + if ((long)KSEGX((unsigned long)to) != (long)CKSEG0 + || (long)KSEGX((unsigned long)from) != (long)CKSEG0) + return copy_page_cpu(to, from); + + page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_L2C_DEST | + M_DM_DSCRA_INTERRUPT; + page_descr[cpu].dscr_b = from_phys | V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE); + __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT))); + + /* + * Don't really want to do it this way, but there's no + * reliable way to delay completion detection. + */ + while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG))) + & M_DM_DSCR_BASE_INTERRUPT)) + ; + __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE))); +} + +#endif /* CONFIG_SIBYTE_DMA_PAGEOPS */ -- cgit v1.2.3