[PATCH 3/3] ARM: msm: Add SMP support for 8960

Rohit Vaswani
2013-06-04T00:21:17Z

Add the cpus bindings and the Krait release sequence
to make SMP work for MSM8960

Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
---
Documentation/devicetree/bindings/arm/cpus.txt | 2 +
Documentation/devicetree/bindings/arm/msm/kpss.txt | 16 ++++++
arch/arm/boot/dts/msm8960-cdp.dts | 22 ++++++++
arch/arm/mach-msm/platsmp.c | 57 ++++++++++++++++++++
arch/arm/mach-msm/scm-boot.h | 8 ++-
5 files changed, 102 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/msm/kpss.txt

diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt
index 327aad2..1132eac 100644
--- a/Documentation/devicetree/bindings/arm/cpus.txt
+++ b/Documentation/devicetree/bindings/arm/cpus.txt
@@ -45,11 +45,13 @@ For the ARM architecture every CPU node must contain the following properties:
"marvell,xsc3"
"marvell,xscale"
"qcom,scorpion"
+ "qcom,krait"
- enable-method: Specifies the method used to enable or take the secondary cores
out of reset. This allows different reset sequence for
different types of cpus.
This should be one of:
"qcom,scss"
+ "qcom,kpssv1"

Example:

diff --git a/Documentation/devicetree/bindings/arm/msm/kpss.txt b/Documentation/devicetree/bindings/arm/msm/kpss.txt
new file mode 100644
index 0000000..7272340
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/msm/kpss.txt
@@ -0,0 +1,16 @@
+* KPSS - Krait Processor Sub-system
+
+Properties
+
+- compatible : Should contain "qcom,kpss".
+
+- reg: Specifies the base address for the KPSS registers used for
+ booting up secondary cores.
+
+Example:
+
+ kpss@2088000 {
+ compatible = "qcom,kpss";
+ reg = <0x02088000 0x1000
+ 0x02098000 0x2000>;
+ };
diff --git a/arch/arm/boot/dts/msm8960-cdp.dts b/arch/arm/boot/dts/msm8960-cdp.dts
index 2e4d87a..fd2f3ec 100644
--- a/arch/arm/boot/dts/msm8960-cdp.dts
+++ b/arch/arm/boot/dts/msm8960-cdp.dts
@@ -7,6 +7,22 @@
compatible = "qcom,msm8960-cdp", "qcom,msm8960";
interrupt-parent = <&intc>;

+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "qcom,krait";
+ device_type = "cpu";
+ enable-method = "qcom,kpssv1";
+
+ cpu@0 {
+ reg = <0>;
+ };
+
+ cpu@1 {
+ reg = <1>;
+ };
+ };
+
intc: interrupt-controller@2000000 {
compatible = "qcom,msm-qgic2";
interrupt-controller;
@@ -26,6 +42,12 @@
cpu-offset = <0x80000>;
};

+ kpss@2088000 {
+ compatible = "qcom,kpss";
+ reg = <0x02088000 0x1000
+ 0x02098000 0x2000>;
+ };
+
serial@19c400000 {
compatible = "qcom,msm-hsuart", "qcom,msm-uart";
reg = <0x16440000 0x1000>,
diff --git a/arch/arm/mach-msm/platsmp.c b/arch/arm/mach-msm/platsmp.c
index ccf4168..2e9e0a1 100644
--- a/arch/arm/mach-msm/platsmp.c
+++ b/arch/arm/mach-msm/platsmp.c
@@ -88,6 +88,56 @@ static int __cpuinit scorpion_release_secondary(void)
return 0;
}

+static int __cpuinit msm8960_release_secondary(unsigned int cpu)
+{
+ void __iomem *reg;
+ struct device_node *dn = NULL;
+
+ if (cpu == 0 || cpu >= num_possible_cpus())
+ return -EINVAL;
+
+ dn = of_find_compatible_node(dn, NULL, "qcom,kpss");
+ if (!dn) {
+ pr_err("%s : Missing kpss node from device tree\n", __func__);
+ return -ENXIO;
+ }
+
+ reg = of_iomap(dn, cpu);
+ if (!reg)
+ return -ENOMEM;
+
+ pr_debug("Starting secondary CPU %d\n", cpu);
+
+ /* Turn on CPU Rail */
+ writel_relaxed(0xA4, reg+0x1014);
+ mb();
+ udelay(512);
+
+ /* Krait bring-up sequence */
+ writel_relaxed(0x109, reg+0x04);
+ writel_relaxed(0x101, reg+0x04);
+ mb();
+ ndelay(300);
+
+ writel_relaxed(0x121, reg+0x04);
+ mb();
+ udelay(2);
+
+ writel_relaxed(0x120, reg+0x04);
+ mb();
+ udelay(2);
+
+ writel_relaxed(0x100, reg+0x04);
+ mb();
+ udelay(100);
+
+ writel_relaxed(0x180, reg+0x04);
+ mb();
+
+ iounmap(reg);
+ return 0;
+}
+
static DEFINE_PER_CPU(int, cold_boot_done);

static __cpuinit void boot_cold_cpu(unsigned int cpu)
@@ -110,6 +160,11 @@ static __cpuinit void boot_cold_cpu(unsigned int cpu)
scorpion_release_secondary();
per_cpu(cold_boot_done, cpu) = true;
}
+ } else if (!strcmp(enable_method, "qcom,kpssv1")) {
+ if (per_cpu(cold_boot_done, cpu) == false) {
+ msm8960_release_secondary(cpu);
+ per_cpu(cold_boot_done, cpu) = true;
+ }
} else {
pr_err("%s: Invalid enable-method property: %s\n",
__func__, enable_method);
@@ -186,6 +241,8 @@ static void __init msm_smp_init_cpus(void)
static const int cold_boot_flags[] __initconst = {
0,
SCM_FLAG_COLDBOOT_CPU1,
+ SCM_FLAG_COLDBOOT_CPU2,
+ SCM_FLAG_COLDBOOT_CPU3,
};

static void __init msm_smp_prepare_cpus(unsigned int max_cpus)
diff --git a/arch/arm/mach-msm/scm-boot.h b/arch/arm/mach-msm/scm-boot.h
index 7be32ff..6aabb24 100644
--- a/arch/arm/mach-msm/scm-boot.h
+++ b/arch/arm/mach-msm/scm-boot.h
@@ -13,9 +13,11 @@
#define __MACH_SCM_BOOT_H

#define SCM_BOOT_ADDR 0x1
-#define SCM_FLAG_COLDBOOT_CPU1 0x1
-#define SCM_FLAG_WARMBOOT_CPU1 0x2
-#define SCM_FLAG_WARMBOOT_CPU0 0x4
+#define SCM_FLAG_COLDBOOT_CPU1 0x01
+#define SCM_FLAG_COLDBOOT_CPU2 0x08
+#define SCM_FLAG_COLDBOOT_CPU3 0x20
+#define SCM_FLAG_WARMBOOT_CPU0 0x04
+#define SCM_FLAG_WARMBOOT_CPU1 0x02

int scm_set_boot_addr(phys_addr_t addr, int flags);