[Add SMP support for Allwinner A20: PATCH V5 1/3] Add smp support for Allwinner A20(sunxi 7i).
From: Fan Rong
Date: Thu Oct 17 2013 - 12:39:11 EST
This patch adds SMP support for the Allwinner A20 SoC. This SoC uses an IP to, among other things, handle the CPU-related configuration, like the power clamp, the boot address of the secondary CPUS, etc. We thus need to map this IP during the prepare_cpu SMP operation, before bringing up the secondary CPU in the secondary_startup operation.
Signed-off-by: Fan Rong <cinifr@xxxxxxxxx>
---
arch/arm/mach-sunxi/Makefile | 2 +
arch/arm/mach-sunxi/headsmp.S | 18 +++++++
arch/arm/mach-sunxi/platsmp.c | 114 ++++++++++++++++++++++++++++++++++++++++++
arch/arm/mach-sunxi/sunxi.c | 3 ++
4 files changed, 137 insertions(+)
create mode 100644 arch/arm/mach-sunxi/headsmp.S
create mode 100644 arch/arm/mach-sunxi/platsmp.c
mode change 100644 => 100755 arch/arm/mach-sunxi/sunxi.c
diff --git a/arch/arm/mach-sunxi/Makefile b/arch/arm/mach-sunxi/Makefile
index 93bebfc..d7f1ef4 100644
--- a/arch/arm/mach-sunxi/Makefile
+++ b/arch/arm/mach-sunxi/Makefile
@@ -1 +1,3 @@
obj-$(CONFIG_ARCH_SUNXI) += sunxi.o
+obj-$(CONFIG_ARCH_SUNXI) += platsmp.o
+obj-$(CONFIG_ARCH_SUNXI) += headsmp.o
diff --git a/arch/arm/mach-sunxi/headsmp.S b/arch/arm/mach-sunxi/headsmp.S
new file mode 100644
index 0000000..48c9d33
--- /dev/null
+++ b/arch/arm/mach-sunxi/headsmp.S
@@ -0,0 +1,18 @@
+/*
+ * SMP support for A20
+ *
+ * Copyright (C) 2013 Fan Rong <cinifr@xxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/linkage.h>
+#include <linux/init.h>
+
+.section ".text.head", "ax"
+ENTRY(sun7i_secondary_startup)
+ msr cpsr_fsxc,#0xd3
+ b secondary_startup
+ENDPROC(sun7i_secondary_startup)
diff --git a/arch/arm/mach-sunxi/platsmp.c b/arch/arm/mach-sunxi/platsmp.c
new file mode 100644
index 0000000..fa5adde
--- /dev/null
+++ b/arch/arm/mach-sunxi/platsmp.c
@@ -0,0 +1,114 @@
+/*
+ * linux/arch/arm/mach-sun7i/platsmp.c
+ *
+ * Copyright (C) 2013 Fan Rong <cinifr@xxxxxxxxx>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/smp.h>
+
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+
+/*
+ * CPU Configure module support
+ * 1: Software reset for smp cpus
+ * 2: Configure for smp cpus including boot.
+ * 3: Three 64-bit idle counters and two 64-bit common counters
+ * it is needed for smp cpus
+ */
+void __iomem *sun7i_cc_base; /*CPU Configure Base*/
+extern void sun7i_secondary_startup(void);
+
+/*
+ * CPUCFG
+ */
+#define SUN7I_CPUCFG_BOOTADDR 0x01a4
+
+#define SUN7I_CPUCFG_GENCTL 0x0184
+#define SUN7I_CPUCFG_DBGCTL0 0x01e0
+#define SUN7I_CPUCFG_DBGCTL1 0x01e4
+
+#define SUN7I_CPU1_PWR_CLAMP 0x01b0
+#define SUN7I_CPU1_PWROFF_REG 0x01b4
+#define SUN7I_CPUX_RESET_CTL(x) (0x40 + (x)*0x40)
+
+static struct of_device_id sun7i_cc_ids[] = {
+ { .compatible = "allwinner,sun7i-a20-cpuconfig"},
+ { /*sentinel*/ }
+};
+
+static int sun7i_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ long paddr;
+ uint32_t pwr_reg;
+ uint32_t j = 0xff << 1;
+ if (!sun7i_cc_base) {
+ pr_debug("error map cpu configure\n");
+ return -ENOSYS;
+ }
+ /* Set boot addr */
+ paddr = virt_to_phys(sun7i_secondary_startup);
+ writel(paddr, sun7i_cc_base + SUN7I_CPUCFG_BOOTADDR);
+
+ /* Assert cpu core reset */
+ writel(0, sun7i_cc_base + SUN7I_CPUX_RESET_CTL(cpu));
+
+ /* Ensure CPU reset also invalidates L1 caches */
+ pwr_reg = readl(sun7i_cc_base + SUN7I_CPUCFG_GENCTL);
+ pwr_reg &= ~BIT(cpu);
+ writel(pwr_reg, sun7i_cc_base + SUN7I_CPUCFG_GENCTL);
+
+ /* DBGPWRDUP hold low */
+ pwr_reg = readl(sun7i_cc_base + SUN7I_CPUCFG_DBGCTL1);
+ pwr_reg &= ~BIT(cpu);
+ writel(pwr_reg, sun7i_cc_base + SUN7I_CPUCFG_DBGCTL1);
+
+ /* Ramp up power to CPU1 */
+ do {
+ writel(j, sun7i_cc_base + SUN7I_CPU1_PWR_CLAMP);
+ j = j >> 1;
+ } while (j != 0);
+
+ mdelay(10);
+
+ pwr_reg = readl(sun7i_cc_base + SUN7I_CPU1_PWROFF_REG);
+ pwr_reg &= ~1;
+ writel(pwr_reg, sun7i_cc_base + SUN7I_CPU1_PWROFF_REG);
+ mdelay(1);
+
+ /* Release CPU reset */
+ writel(3, sun7i_cc_base + SUN7I_CPUX_RESET_CTL(cpu));
+
+ /* Unlock CPU */
+ pwr_reg = readl(sun7i_cc_base + SUN7I_CPUCFG_DBGCTL1);
+ pwr_reg |= BIT(cpu);
+ writel(pwr_reg, sun7i_cc_base + SUN7I_CPUCFG_DBGCTL1);
+
+ return 0;
+}
+
+static void __init sun7i_init_cpuconfig_map(unsigned int max_cpus)
+{
+ struct device_node *np;
+ np = of_find_matching_node(NULL, sun7i_cc_ids);
+ if (WARN(!np, "unable to setup cup configure"))
+ return;
+ sun7i_cc_base = of_iomap(np, 0);
+ if (WARN(!sun7i_cc_base, "failed to map cup configure base address"))
+ return;
+}
+
+struct smp_operations sun7i_smp_ops __initdata = {
+ .smp_boot_secondary = sun7i_boot_secondary,
+ .smp_prepare_cpus = sun7i_init_cpuconfig_map,
+};
diff --git a/arch/arm/mach-sunxi/sunxi.c b/arch/arm/mach-sunxi/sunxi.c
old mode 100644
new mode 100755
index f184f6c..545269d
--- a/arch/arm/mach-sunxi/sunxi.c
+++ b/arch/arm/mach-sunxi/sunxi.c
@@ -26,6 +26,8 @@
#include <asm/mach/map.h>
#include <asm/system_misc.h>
+extern struct smp_operations sun7i_smp_ops;
+
#define SUN4I_WATCHDOG_CTRL_REG 0x00
#define SUN4I_WATCHDOG_CTRL_RESTART BIT(0)
#define SUN4I_WATCHDOG_MODE_REG 0x04
@@ -155,6 +157,7 @@ static const char * const sun7i_board_dt_compat[] = {
};
DT_MACHINE_START(SUN7I_DT, "Allwinner sun7i (A20) Family")
+ .smp = smp_ops(sun7i_smp_ops),
.init_machine = sunxi_dt_init,
.init_time = sunxi_timer_init,
.dt_compat = sun7i_board_dt_compat,
--
1.8.1.2
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