soc: brcmstb: biuctrl: Fine tune B53 MCP interface settings

In order to achieve expected MCP bus throughput on 3 particular chips:
7268, 7271 and 7278, do the appropriate programming of the MCP
interface: increase number of MCP write credits, turn on write-back
throttling when present.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
This commit is contained in:
Florian Fainelli 2017-02-27 17:35:03 -08:00
parent 6451d644b8
commit b4b32e3216

View File

@ -22,6 +22,18 @@
#include <linux/soc/brcmstb/brcmstb.h>
#define CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK 0x70000000
#define CPU_CREDIT_REG_MCPx_READ_CRED_MASK 0xf
#define CPU_CREDIT_REG_MCPx_WRITE_CRED_MASK 0xf
#define CPU_CREDIT_REG_MCPx_READ_CRED_SHIFT(x) ((x) * 8)
#define CPU_CREDIT_REG_MCPx_WRITE_CRED_SHIFT(x) (((x) * 8) + 4)
#define CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_SHIFT(x) ((x) * 8)
#define CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_MASK 0xff
#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_THRESHOLD_MASK 0xf
#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_MASK 0xf
#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_SHIFT 4
#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_ENABLE BIT(8)
static void __iomem *cpubiuctrl_base;
static bool mcp_wr_pairing_en;
@ -59,6 +71,13 @@ static const int b15_cpubiuctrl_regs[] = {
[CPU_WRITEBACK_CTRL_REG] = -1,
};
/* Odd cases, e.g: 7260 */
static const int b53_cpubiuctrl_no_wb_regs[] = {
[CPU_CREDIT_REG] = 0x0b0,
[CPU_MCP_FLOW_REG] = 0x0b4,
[CPU_WRITEBACK_CTRL_REG] = -1,
};
static const int b53_cpubiuctrl_regs[] = {
[CPU_CREDIT_REG] = 0x0b0,
[CPU_MCP_FLOW_REG] = 0x0b4,
@ -90,6 +109,59 @@ static int __init mcp_write_pairing_set(void)
return 0;
}
static const u32 b53_mach_compat[] = {
0x7268,
0x7271,
0x7278,
};
static void __init mcp_b53_set(void)
{
unsigned int i;
u32 reg;
reg = brcmstb_get_family_id();
for (i = 0; i < ARRAY_SIZE(b53_mach_compat); i++) {
if (BRCM_ID(reg) == b53_mach_compat[i])
break;
}
if (i == ARRAY_SIZE(b53_mach_compat))
return;
/* Set all 3 MCP interfaces to 8 credits */
reg = cbc_readl(CPU_CREDIT_REG);
for (i = 0; i < 3; i++) {
reg &= ~(CPU_CREDIT_REG_MCPx_WRITE_CRED_MASK <<
CPU_CREDIT_REG_MCPx_WRITE_CRED_SHIFT(i));
reg &= ~(CPU_CREDIT_REG_MCPx_READ_CRED_MASK <<
CPU_CREDIT_REG_MCPx_READ_CRED_SHIFT(i));
reg |= 8 << CPU_CREDIT_REG_MCPx_WRITE_CRED_SHIFT(i);
reg |= 8 << CPU_CREDIT_REG_MCPx_READ_CRED_SHIFT(i);
}
cbc_writel(reg, CPU_CREDIT_REG);
/* Max out the number of in-flight Jwords reads on the MCP interface */
reg = cbc_readl(CPU_MCP_FLOW_REG);
for (i = 0; i < 3; i++)
reg |= CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_MASK <<
CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_SHIFT(i);
cbc_writel(reg, CPU_MCP_FLOW_REG);
/* Enable writeback throttling, set timeout to 128 cycles, 256 cycles
* threshold
*/
reg = cbc_readl(CPU_WRITEBACK_CTRL_REG);
reg |= CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_ENABLE;
reg &= ~CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_THRESHOLD_MASK;
reg &= ~(CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_MASK <<
CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_SHIFT);
reg |= 8;
reg |= 7 << CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_SHIFT;
cbc_writel(reg, CPU_WRITEBACK_CTRL_REG);
}
static int __init setup_hifcpubiuctrl_regs(void)
{
struct device_node *np, *cpu_dn;
@ -126,6 +198,9 @@ static int __init setup_hifcpubiuctrl_regs(void)
ret = -EINVAL;
}
of_node_put(cpu_dn);
if (BRCM_ID(brcmstb_get_family_id()) == 0x7260)
cpubiuctrl_regs = b53_cpubiuctrl_no_wb_regs;
out:
of_node_put(np);
return ret;
@ -177,6 +252,7 @@ void __init brcmstb_biuctrl_init(void)
return;
}
mcp_b53_set();
#ifdef CONFIG_PM_SLEEP
register_syscore_ops(&brcmstb_cpu_credit_syscore_ops);
#endif