linux/arch/mips/mm/page.c
Shinya Kuribayashi a644b2774d MIPS: NEC VR5500 processor support fixup
Current VR5500 processor support lacks of some functions which are
expected to be configured/synthesized on arch initialization.

Here're some VR5500A spec notes:

* All execution hazards are handled in hardware.

* Once VR5500A stops the operation of the pipeline by WAIT instruction,
  it could return from the standby mode only when either a reset, NMI
  request, or all enabled interrupts is/are detected.  In other words,
  if interrupts are disabled by Status.IE=0, it keeps in standby mode
  even when interrupts are internally asserted.

  Notes on WAIT: The operation of the processor is undefined if WAIT
  insn is in the branch delay slot.  The operation is also undefined
  if WAIT insn is executed when Status.EXL and Status.ERL are set to 1.

* VR5500A core only implements the Load prefetch.

With these changes, it boots fine.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-03-11 21:11:07 +01:00

690 lines
19 KiB
C

/*
* 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 <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>
#ifdef CONFIG_SIBYTE_DMA_PAGEOPS
#include <asm/sibyte/sb1250.h>
#include <asm/sibyte/sb1250_regs.h>
#include <asm/sibyte/sb1250_dma.h>
#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_R5500:
case CPU_TX49XX:
/* These processors only support the 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.
*/
half_clear_loop_size = min(16 * clear_word_size,
max(cache_line_size >> 1,
4 * clear_word_size));
half_copy_loop_size = min(16 * 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 (cache_line_size == (half_clear_loop_size << 1)) {
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 = cache_line_size ? min(8, pref_bias_clear_store / cache_line_size)
* cache_line_size : 0;
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 (cache_line_size == (half_copy_loop_size << 1)) {
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 *)&copy_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 = cache_line_size ? min(8, pref_bias_copy_load / cache_line_size) *
cache_line_size : 0;
while (off) {
build_copy_load_pref(&buf, -off);
off -= cache_line_size;
}
off = cache_line_size ? min(8, pref_bias_copy_store / cache_line_size) *
cache_line_size : 0;
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 */