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Diffstat (limited to 'arch/arm/mach-sunxi/platsmp.c')
-rw-r--r--arch/arm/mach-sunxi/platsmp.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/arch/arm/mach-sunxi/platsmp.c b/arch/arm/mach-sunxi/platsmp.c
new file mode 100644
index 000000000000..7b141d8342a1
--- /dev/null
+++ b/arch/arm/mach-sunxi/platsmp.c
@@ -0,0 +1,124 @@
+/*
+ * SMP support for Allwinner SoCs
+ *
+ * Copyright (C) 2013 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * Based on code
+ * Copyright (C) 2012-2013 Allwinner Ltd.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/memory.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/smp.h>
+
+#include "common.h"
+
+#define CPUCFG_CPU_PWR_CLAMP_STATUS_REG(cpu) ((cpu) * 0x40 + 0x64)
+#define CPUCFG_CPU_RST_CTRL_REG(cpu) (((cpu) + 1) * 0x40)
+#define CPUCFG_CPU_CTRL_REG(cpu) (((cpu) + 1) * 0x40 + 0x04)
+#define CPUCFG_CPU_STATUS_REG(cpu) (((cpu) + 1) * 0x40 + 0x08)
+#define CPUCFG_GEN_CTRL_REG 0x184
+#define CPUCFG_PRIVATE0_REG 0x1a4
+#define CPUCFG_PRIVATE1_REG 0x1a8
+#define CPUCFG_DBG_CTL0_REG 0x1e0
+#define CPUCFG_DBG_CTL1_REG 0x1e4
+
+#define PRCM_CPU_PWROFF_REG 0x100
+#define PRCM_CPU_PWR_CLAMP_REG(cpu) (((cpu) * 4) + 0x140)
+
+static void __iomem *cpucfg_membase;
+static void __iomem *prcm_membase;
+
+static DEFINE_SPINLOCK(cpu_lock);
+
+static void __init sun6i_smp_prepare_cpus(unsigned int max_cpus)
+{
+ struct device_node *node;
+
+ node = of_find_compatible_node(NULL, NULL, "allwinner,sun6i-a31-prcm");
+ if (!node) {
+ pr_err("Missing A31 PRCM node in the device tree\n");
+ return;
+ }
+
+ prcm_membase = of_iomap(node, 0);
+ if (!prcm_membase) {
+ pr_err("Couldn't map A31 PRCM registers\n");
+ return;
+ }
+
+ node = of_find_compatible_node(NULL, NULL,
+ "allwinner,sun6i-a31-cpuconfig");
+ if (!node) {
+ pr_err("Missing A31 CPU config node in the device tree\n");
+ return;
+ }
+
+ cpucfg_membase = of_iomap(node, 0);
+ if (!cpucfg_membase)
+ pr_err("Couldn't map A31 CPU config registers\n");
+
+}
+
+static int sun6i_smp_boot_secondary(unsigned int cpu,
+ struct task_struct *idle)
+{
+ u32 reg;
+ int i;
+
+ if (!(prcm_membase && cpucfg_membase))
+ return -EFAULT;
+
+ spin_lock(&cpu_lock);
+
+ /* Set CPU boot address */
+ writel(virt_to_phys(sun6i_secondary_startup),
+ cpucfg_membase + CPUCFG_PRIVATE0_REG);
+
+ /* Assert the CPU core in reset */
+ writel(0, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
+
+ /* Assert the L1 cache in reset */
+ reg = readl(cpucfg_membase + CPUCFG_GEN_CTRL_REG);
+ writel(reg & ~BIT(cpu), cpucfg_membase + CPUCFG_GEN_CTRL_REG);
+
+ /* Disable external debug access */
+ reg = readl(cpucfg_membase + CPUCFG_DBG_CTL1_REG);
+ writel(reg & ~BIT(cpu), cpucfg_membase + CPUCFG_DBG_CTL1_REG);
+
+ /* Power up the CPU */
+ for (i = 0; i <= 8; i++)
+ writel(0xff >> i, prcm_membase + PRCM_CPU_PWR_CLAMP_REG(cpu));
+ mdelay(10);
+
+ /* Clear CPU power-off gating */
+ reg = readl(prcm_membase + PRCM_CPU_PWROFF_REG);
+ writel(reg & ~BIT(cpu), prcm_membase + PRCM_CPU_PWROFF_REG);
+ mdelay(1);
+
+ /* Deassert the CPU core reset */
+ writel(3, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
+
+ /* Enable back the external debug accesses */
+ reg = readl(cpucfg_membase + CPUCFG_DBG_CTL1_REG);
+ writel(reg | BIT(cpu), cpucfg_membase + CPUCFG_DBG_CTL1_REG);
+
+ spin_unlock(&cpu_lock);
+
+ return 0;
+}
+
+struct smp_operations sun6i_smp_ops __initdata = {
+ .smp_prepare_cpus = sun6i_smp_prepare_cpus,
+ .smp_boot_secondary = sun6i_smp_boot_secondary,
+};