soc: bcm: brcmstb: biuctrl: Change RAC prefetch distance from +/-1 to +/- 2

Change the RAC prefetch distance from +/- 1 to +/- 2 for Cortex-A72 CPUs
since this provides an average of a 3.8% performance increase for
synthetic memcpy benchmarks.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
This commit is contained in:
Florian Fainelli 2019-10-25 11:18:06 -07:00
parent 4029f3b419
commit 091353c88b

View File

@ -20,6 +20,8 @@
#define RACENDATA_SHIFT 6
#define RAC_CPU_SHIFT 8
#define RACCFG_MASK 0xff
#define DPREF_LINE_2_SHIFT 24
#define DPREF_LINE_2_MASK 0xff
/* Bitmask to enable instruction and data prefetching with a 256-bytes stride */
#define RAC_DATA_INST_EN_MASK (1 << RACPREFINST_SHIFT | \
@ -50,6 +52,7 @@ enum cpubiuctrl_regs {
CPU_MCP_FLOW_REG,
CPU_WRITEBACK_CTRL_REG,
RAC_CONFIG0_REG,
RAC_CONFIG1_REG,
NUM_CPU_BIUCTRL_REGS,
};
@ -58,7 +61,7 @@ static inline u32 cbc_readl(int reg)
int offset = cpubiuctrl_regs[reg];
if (offset == -1 ||
(IS_ENABLED(CONFIG_CACHE_B15_RAC) && reg == RAC_CONFIG0_REG))
(IS_ENABLED(CONFIG_CACHE_B15_RAC) && reg >= RAC_CONFIG0_REG))
return (u32)-1;
return readl_relaxed(cpubiuctrl_base + offset);
@ -69,7 +72,7 @@ static inline void cbc_writel(u32 val, int reg)
int offset = cpubiuctrl_regs[reg];
if (offset == -1 ||
(IS_ENABLED(CONFIG_CACHE_B15_RAC) && reg == RAC_CONFIG0_REG))
(IS_ENABLED(CONFIG_CACHE_B15_RAC) && reg >= RAC_CONFIG0_REG))
return;
writel(val, cpubiuctrl_base + offset);
@ -80,6 +83,7 @@ static const int b15_cpubiuctrl_regs[] = {
[CPU_MCP_FLOW_REG] = -1,
[CPU_WRITEBACK_CTRL_REG] = -1,
[RAC_CONFIG0_REG] = -1,
[RAC_CONFIG1_REG] = -1,
};
/* Odd cases, e.g: 7260A0 */
@ -88,6 +92,7 @@ static const int b53_cpubiuctrl_no_wb_regs[] = {
[CPU_MCP_FLOW_REG] = 0x0b4,
[CPU_WRITEBACK_CTRL_REG] = -1,
[RAC_CONFIG0_REG] = 0x78,
[RAC_CONFIG1_REG] = 0x7c,
};
static const int b53_cpubiuctrl_regs[] = {
@ -95,6 +100,7 @@ static const int b53_cpubiuctrl_regs[] = {
[CPU_MCP_FLOW_REG] = 0x0b4,
[CPU_WRITEBACK_CTRL_REG] = 0x22c,
[RAC_CONFIG0_REG] = 0x78,
[RAC_CONFIG1_REG] = 0x7c,
};
static const int a72_cpubiuctrl_regs[] = {
@ -102,6 +108,7 @@ static const int a72_cpubiuctrl_regs[] = {
[CPU_MCP_FLOW_REG] = 0x1c,
[CPU_WRITEBACK_CTRL_REG] = 0x20,
[RAC_CONFIG0_REG] = 0x08,
[RAC_CONFIG1_REG] = 0x0c,
};
static int __init mcp_write_pairing_set(void)
@ -167,7 +174,7 @@ static const u32 a72_b53_mach_compat[] = {
static void __init a72_b53_rac_enable_all(struct device_node *np)
{
unsigned int cpu;
u32 enable = 0;
u32 enable = 0, pref_dist;
if (IS_ENABLED(CONFIG_CACHE_B15_RAC))
return;
@ -175,10 +182,15 @@ static void __init a72_b53_rac_enable_all(struct device_node *np)
if (WARN(num_possible_cpus() > 4, "RAC only supports 4 CPUs\n"))
return;
for_each_possible_cpu(cpu)
pref_dist = cbc_readl(RAC_CONFIG1_REG);
for_each_possible_cpu(cpu) {
enable |= RAC_DATA_INST_EN_MASK << (cpu * RAC_CPU_SHIFT);
if (cpubiuctrl_regs == a72_cpubiuctrl_regs)
pref_dist |= 1 << (cpu + DPREF_LINE_2_SHIFT);
}
cbc_writel(enable, RAC_CONFIG0_REG);
cbc_writel(pref_dist, RAC_CONFIG1_REG);
pr_info("%pOF: Broadcom %s read-ahead cache\n",
np, cpubiuctrl_regs == a72_cpubiuctrl_regs ?