[PATCH v4 2/5] ARM: BCM: Clean up SMP support for Broadcom Kona
Kapil Hali
kapilh at broadcom.com
Tue Dec 1 08:24:06 PST 2015
These changes cleans up SMP implementaion for Broadcom's
Kona SoC which are required for handling SMP for iProc
family of SoCs at a single place for BCM NSP and BCM Kona.
Signed-off-by: Kapil Hali <kapilh at broadcom.com>
---
arch/arm/boot/dts/bcm11351.dtsi | 2 +-
arch/arm/boot/dts/bcm21664.dtsi | 2 +-
arch/arm/mach-bcm/kona_smp.c | 82 +++++++++++++++++++++++++++--------------
3 files changed, 56 insertions(+), 30 deletions(-)
diff --git a/arch/arm/boot/dts/bcm11351.dtsi b/arch/arm/boot/dts/bcm11351.dtsi
index 2ddaa51..3dc7a8c 100644
--- a/arch/arm/boot/dts/bcm11351.dtsi
+++ b/arch/arm/boot/dts/bcm11351.dtsi
@@ -31,7 +31,6 @@
#address-cells = <1>;
#size-cells = <0>;
enable-method = "brcm,bcm11351-cpu-method";
- secondary-boot-reg = <0x3500417c>;
cpu0: cpu at 0 {
device_type = "cpu";
@@ -42,6 +41,7 @@
cpu1: cpu at 1 {
device_type = "cpu";
compatible = "arm,cortex-a9";
+ secondary-boot-reg = <0x3500417c>;
reg = <1>;
};
};
diff --git a/arch/arm/boot/dts/bcm21664.dtsi b/arch/arm/boot/dts/bcm21664.dtsi
index 2016b72..3f525be 100644
--- a/arch/arm/boot/dts/bcm21664.dtsi
+++ b/arch/arm/boot/dts/bcm21664.dtsi
@@ -31,7 +31,6 @@
#address-cells = <1>;
#size-cells = <0>;
enable-method = "brcm,bcm11351-cpu-method";
- secondary-boot-reg = <0x35004178>;
cpu0: cpu at 0 {
device_type = "cpu";
@@ -42,6 +41,7 @@
cpu1: cpu at 1 {
device_type = "cpu";
compatible = "arm,cortex-a9";
+ secondary-boot-reg = <0x35004178>;
reg = <1>;
};
};
diff --git a/arch/arm/mach-bcm/kona_smp.c b/arch/arm/mach-bcm/kona_smp.c
index 66a0465..15af781 100644
--- a/arch/arm/mach-bcm/kona_smp.c
+++ b/arch/arm/mach-bcm/kona_smp.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2014 Broadcom Corporation
+ * Copyright (C) 2014-2015 Broadcom Corporation
* Copyright 2014 Linaro Limited
*
* This program is free software; you can redistribute it and/or
@@ -30,9 +30,10 @@
/* Name of device node property defining secondary boot register location */
#define OF_SECONDARY_BOOT "secondary-boot-reg"
+#define MPIDR_CPUID_BITMASK 0x3
/* I/O address of register used to coordinate secondary core startup */
-static u32 secondary_boot;
+static u32 secondary_boot_addr;
/*
* Enable the Cortex A9 Snoop Control Unit
@@ -78,44 +79,68 @@ static int __init scu_a9_enable(void)
static void __init bcm_smp_prepare_cpus(unsigned int max_cpus)
{
static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 };
- struct device_node *node;
+ struct device_node *cpus_node = NULL;
+ struct device_node *cpu_node = NULL;
int ret;
- BUG_ON(secondary_boot); /* We're called only once */
-
/*
* This function is only called via smp_ops->smp_prepare_cpu().
* That only happens if a "/cpus" device tree node exists
* and has an "enable-method" property that selects the SMP
* operations defined herein.
*/
- node = of_find_node_by_path("/cpus");
- BUG_ON(!node);
-
- /*
- * Our secondary enable method requires a "secondary-boot-reg"
- * property to specify a register address used to request the
- * ROM code boot a secondary code. If we have any trouble
- * getting this we fall back to uniprocessor mode.
- */
- if (of_property_read_u32(node, OF_SECONDARY_BOOT, &secondary_boot)) {
- pr_err("%s: missing/invalid " OF_SECONDARY_BOOT " property\n",
- node->name);
- ret = -ENOENT; /* Arrange to disable SMP */
- goto out;
+ cpus_node = of_find_node_by_path("/cpus");
+ if (!cpus_node)
+ return;
+
+ for_each_child_of_node(cpus_node, cpu_node) {
+ u32 cpuid;
+
+ if (of_node_cmp(cpu_node->type, "cpu"))
+ continue;
+
+ if (of_property_read_u32(cpu_node, "reg", &cpuid)) {
+ pr_debug("%s: missing reg property\n",
+ cpu_node->full_name);
+ ret = -ENOENT;
+ goto out;
+ }
+
+ /*
+ * "secondary-boot-reg" property should be defined only
+ * for secondary cpu
+ */
+ if ((cpuid & MPIDR_CPUID_BITMASK) == 1) {
+ /*
+ * Our secondary enable method requires a
+ * "secondary-boot-reg" property to specify a register
+ * address used to request the ROM code boot a secondary
+ * core. If we have any trouble getting this we fall
+ * back to uniprocessor mode.
+ */
+ if (of_property_read_u32(cpu_node,
+ OF_SECONDARY_BOOT,
+ &secondary_boot_addr)) {
+ pr_warn("%s: no" OF_SECONDARY_BOOT "property\n",
+ cpu_node->name);
+ ret = -ENOENT;
+ goto out;
+ }
+ }
}
/*
- * Enable the SCU on Cortex A9 based SoCs. If -ENOENT is
+ * Enable the SCU on Cortex A9 based SoCs. If -ENOENT is
* returned, the SoC reported a uniprocessor configuration.
* We bail on any other error.
*/
ret = scu_a9_enable();
out:
- of_node_put(node);
+ of_node_put(cpu_node);
+ of_node_put(cpus_node);
+
if (ret) {
/* Update the CPU present map to reflect uniprocessor mode */
- BUG_ON(ret != -ENOENT);
pr_warn("disabling SMP\n");
init_cpu_present(&only_cpu_0);
}
@@ -139,7 +164,7 @@ out:
* - Wait for the secondary boot register to be re-written, which
* indicates the secondary core has started.
*/
-static int bcm_boot_secondary(unsigned int cpu, struct task_struct *idle)
+static int kona_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
void __iomem *boot_reg;
phys_addr_t boot_func;
@@ -154,15 +179,16 @@ static int bcm_boot_secondary(unsigned int cpu, struct task_struct *idle)
return -EINVAL;
}
- if (!secondary_boot) {
+ if (!secondary_boot_addr) {
pr_err("required secondary boot register not specified\n");
return -EINVAL;
}
- boot_reg = ioremap_nocache((phys_addr_t)secondary_boot, sizeof(u32));
+ boot_reg = ioremap_nocache(
+ (phys_addr_t)secondary_boot_addr, sizeof(u32));
if (!boot_reg) {
pr_err("unable to map boot register for cpu %u\n", cpu_id);
- return -ENOSYS;
+ return -ENOMEM;
}
/*
@@ -191,12 +217,12 @@ static int bcm_boot_secondary(unsigned int cpu, struct task_struct *idle)
pr_err("timeout waiting for cpu %u to start\n", cpu_id);
- return -ENOSYS;
+ return -ENXIO;
}
static struct smp_operations bcm_smp_ops __initdata = {
.smp_prepare_cpus = bcm_smp_prepare_cpus,
- .smp_boot_secondary = bcm_boot_secondary,
+ .smp_boot_secondary = kona_boot_secondary,
};
CPU_METHOD_OF_DECLARE(bcm_smp_bcm281xx, "brcm,bcm11351-cpu-method",
&bcm_smp_ops);
--
2.1.0
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