arc: cache - utilize IO coherency (AKA IOC) engine

With release of ARC HS38 v2.1 new IO coherency engine could be built-in
ARC core. This hardware module ensures coherency between DMA-ed data
from peripherals and L2 cache.

With L2 and IOC enabled there's no overhead for L2 cache manual
maintenance which results in significantly improved IO bandwidth.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
This commit is contained in:
Alexey Brodkin 2015-12-14 17:15:13 +03:00 committed by Alexey Brodkin
parent 379b3280b3
commit db6ce2312d
2 changed files with 58 additions and 8 deletions

View File

@ -53,6 +53,13 @@
#define ARC_AUX_SLC_INVALIDATE 0x905 #define ARC_AUX_SLC_INVALIDATE 0x905
#define ARC_AUX_SLC_IVDL 0x910 #define ARC_AUX_SLC_IVDL 0x910
#define ARC_AUX_SLC_FLDL 0x912 #define ARC_AUX_SLC_FLDL 0x912
#define ARC_BCR_CLUSTER 0xcf
/* IO coherency related auxiliary registers */
#define ARC_AUX_IO_COH_ENABLE 0x500
#define ARC_AUX_IO_COH_PARTIAL 0x501
#define ARC_AUX_IO_COH_AP0_BASE 0x508
#define ARC_AUX_IO_COH_AP0_SIZE 0x509
#ifndef __ASSEMBLY__ #ifndef __ASSEMBLY__
/* Accessors for auxiliary registers */ /* Accessors for auxiliary registers */

View File

@ -39,6 +39,7 @@ int icache_exists __section(".data");
#ifdef CONFIG_ISA_ARCV2 #ifdef CONFIG_ISA_ARCV2
int slc_line_sz __section(".data"); int slc_line_sz __section(".data");
int slc_exists __section(".data"); int slc_exists __section(".data");
int ioc_exists __section(".data");
static unsigned int __before_slc_op(const int op) static unsigned int __before_slc_op(const int op)
{ {
@ -147,6 +148,21 @@ static void read_decode_cache_bcr_arcv2(void)
slc_exists = 1; slc_exists = 1;
slc_line_sz = (slc_cfg.fields.lsz == 0) ? 128 : 64; slc_line_sz = (slc_cfg.fields.lsz == 0) ? 128 : 64;
} }
union {
struct bcr_clust_cfg {
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int pad:7, c:1, num_entries:8, num_cores:8, ver:8;
#else
unsigned int ver:8, num_cores:8, num_entries:8, c:1, pad:7;
#endif
} fields;
unsigned int word;
} cbcr;
cbcr.word = read_aux_reg(ARC_BCR_CLUSTER);
if (cbcr.fields.c)
ioc_exists = 1;
} }
#endif #endif
@ -191,6 +207,17 @@ void cache_init(void)
#ifdef CONFIG_ISA_ARCV2 #ifdef CONFIG_ISA_ARCV2
read_decode_cache_bcr_arcv2(); read_decode_cache_bcr_arcv2();
if (ioc_exists) {
/* IO coherency base - 0x8z */
write_aux_reg(ARC_AUX_IO_COH_AP0_BASE, 0x80000);
/* IO coherency aperture size - 512Mb: 0x8z-0xAz */
write_aux_reg(ARC_AUX_IO_COH_AP0_SIZE, 0x11);
/* Enable partial writes */
write_aux_reg(ARC_AUX_IO_COH_PARTIAL, 1);
/* Enable IO coherency */
write_aux_reg(ARC_AUX_IO_COH_ENABLE, 1);
}
#endif #endif
} }
@ -359,18 +386,26 @@ static inline void __dc_line_op(unsigned long paddr, unsigned long sz,
void invalidate_dcache_range(unsigned long start, unsigned long end) void invalidate_dcache_range(unsigned long start, unsigned long end)
{ {
__dc_line_op(start, end - start, OP_INV);
#ifdef CONFIG_ISA_ARCV2 #ifdef CONFIG_ISA_ARCV2
if (slc_exists) if (!ioc_exists)
#endif
__dc_line_op(start, end - start, OP_INV);
#ifdef CONFIG_ISA_ARCV2
if (slc_exists && !ioc_exists)
__slc_line_op(start, end - start, OP_INV); __slc_line_op(start, end - start, OP_INV);
#endif #endif
} }
void flush_dcache_range(unsigned long start, unsigned long end) void flush_dcache_range(unsigned long start, unsigned long end)
{ {
__dc_line_op(start, end - start, OP_FLUSH);
#ifdef CONFIG_ISA_ARCV2 #ifdef CONFIG_ISA_ARCV2
if (slc_exists) if (!ioc_exists)
#endif
__dc_line_op(start, end - start, OP_FLUSH);
#ifdef CONFIG_ISA_ARCV2
if (slc_exists && !ioc_exists)
__slc_line_op(start, end - start, OP_FLUSH); __slc_line_op(start, end - start, OP_FLUSH);
#endif #endif
} }
@ -382,18 +417,26 @@ void flush_cache(unsigned long start, unsigned long size)
void invalidate_dcache_all(void) void invalidate_dcache_all(void)
{ {
__dc_entire_op(OP_INV);
#ifdef CONFIG_ISA_ARCV2 #ifdef CONFIG_ISA_ARCV2
if (slc_exists) if (!ioc_exists)
#endif
__dc_entire_op(OP_INV);
#ifdef CONFIG_ISA_ARCV2
if (slc_exists && !ioc_exists)
__slc_entire_op(OP_INV); __slc_entire_op(OP_INV);
#endif #endif
} }
void flush_dcache_all(void) void flush_dcache_all(void)
{ {
__dc_entire_op(OP_FLUSH);
#ifdef CONFIG_ISA_ARCV2 #ifdef CONFIG_ISA_ARCV2
if (slc_exists) if (!ioc_exists)
#endif
__dc_entire_op(OP_FLUSH);
#ifdef CONFIG_ISA_ARCV2
if (slc_exists && !ioc_exists)
__slc_entire_op(OP_FLUSH); __slc_entire_op(OP_FLUSH);
#endif #endif
} }