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@xxxxxxxxx>
---
drivers/soc/bcm/brcmstb/biuctrl.c | 76 +++++++++++++++++++++++++++++++++++++++
1 file changed, 76 insertions(+)
diff --git a/drivers/soc/bcm/brcmstb/biuctrl.c b/drivers/soc/bcm/brcmstb/biuctrl.c
index d498f9db01ab..dd45bbfe64dd 100644
--- a/drivers/soc/bcm/brcmstb/biuctrl.c
+++ b/drivers/soc/bcm/brcmstb/biuctrl.c
@@ -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
--
2.9.3
--
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