[PATCH v4 6/7] ARM: zx: enable SMP and hotplug for zx296702

Jun Nie
2015-04-28T09:18:10Z

Bring up the secondary core. Enable hotplug with supporting
powering off secondary core.

Signed-off-by: Jun Nie <jun.nie@linaro.org>
---
arch/arm/mach-zx/Makefile | 1 +
arch/arm/mach-zx/core.h | 19 +++++
arch/arm/mach-zx/headsmp.S | 32 ++++++++
arch/arm/mach-zx/platsmp.c | 189 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 241 insertions(+)
create mode 100644 arch/arm/mach-zx/core.h
create mode 100644 arch/arm/mach-zx/headsmp.S
create mode 100644 arch/arm/mach-zx/platsmp.c

diff --git a/arch/arm/mach-zx/Makefile b/arch/arm/mach-zx/Makefile
index 7a541c7..7c2edf6 100644
--- a/arch/arm/mach-zx/Makefile
+++ b/arch/arm/mach-zx/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_SOC_ZX296702) += zx296702.o
+obj-$(CONFIG_SMP) += headsmp.o platsmp.o
diff --git a/arch/arm/mach-zx/core.h b/arch/arm/mach-zx/core.h
new file mode 100644
index 0000000..3efe8e0
--- /dev/null
+++ b/arch/arm/mach-zx/core.h
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2014 Linaro Ltd.
+ * Copyright (C) 2014 ZTE Corporation.
+ *
+ * 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.
+ */
+
+#ifndef __MACH_ZX_CORE_H
+#define __MACH_ZX_CORE_H
+
+extern void zx_resume_jump(void);
+extern size_t zx_suspend_iram_sz;
+extern unsigned long zx_secondary_startup_pa;
+
+void zx_secondary_startup(void);
+
+#endif /* __MACH_ZX_CORE_H */
diff --git a/arch/arm/mach-zx/headsmp.S b/arch/arm/mach-zx/headsmp.S
new file mode 100644
index 0000000..c0fece0
--- /dev/null
+++ b/arch/arm/mach-zx/headsmp.S
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2014 Linaro Ltd.
+ * Copyright (C) 2014 ZTE Corporation.
+ *
+ * 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>
+
+ .align 3
+
+/* It runs from physical address */
+ENTRY(zx_resume_jump)
+ adr r1, zx_secondary_startup_pa
+ ldr r0, [r1]
+ bx r0
+ENDPROC(zx_resume_jump)
+
+ENTRY(zx_secondary_startup_pa)
+ .word zx_secondary_startup_pa
+
+ENTRY(zx_suspend_iram_sz)
+ .word . - zx_resume_jump
+ENDPROC(zx_secondary_startup_pa)
+
+
+ENTRY(zx_secondary_startup)
+ bl v7_invalidate_l1
+ b secondary_startup
+ENDPROC(zx_secondary_startup)
diff --git a/arch/arm/mach-zx/platsmp.c b/arch/arm/mach-zx/platsmp.c
new file mode 100644
index 0000000..a369398
--- /dev/null
+++ b/arch/arm/mach-zx/platsmp.c
@@ -0,0 +1,189 @@
+/*
+ * Copyright 2014 Linaro Ltd.
+ * Copyright (C) 2014 ZTE Corporation.
+ *
+ * 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/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/smp.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/fncpy.h>
+#include <asm/proc-fns.h>
+#include <asm/smp_scu.h>
+#include <asm/smp_plat.h>
+
+#include "core.h"
+
+#define AON_SYS_CTRL_RESERVED1 0xa8
+
+#define BUS_MATRIX_REMAP_CONFIG 0x00
+
+#define PCU_CPU0_CTRL 0x00
+#define PCU_CPU1_CTRL 0x04
+#define PCU_CPU1_ST 0x0c
+#define PCU_GLOBAL_CTRL 0x14
+#define PCU_EXPEND_CONTROL 0x34
+
+#define ZX_IRAM_BASE 0x00200000
+
+static void __iomem *pcu_base;
+static void __iomem *matrix_base;
+static void __iomem *scu_base;
+
+void __init zx_smp_prepare_cpus(unsigned int max_cpus)
+{
+ struct device_node *np;
+ unsigned long base = 0;
+ void __iomem *aonsysctrl_base;
+ void __iomem *sys_iram;
+
+ base = scu_a9_get_base();
+ scu_base = ioremap(base, SZ_256);
+ if (!scu_base) {
+ pr_err("%s: failed to map scu\n", __func__);
+ return;
+ }
+
+ scu_enable(scu_base);
+
+ np = of_find_compatible_node(NULL, NULL, "zte,sysctrl");
+ if (!np) {
+ pr_err("%s: failed to find sysctrl node\n", __func__);
+ return;
+ }
+
+ aonsysctrl_base = of_iomap(np, 0);
+ if (!aonsysctrl_base) {
+ pr_err("%s: failed to map aonsysctrl\n", __func__);
+ of_node_put(np);
+ return;
+ }
+
+ /*
+ * Write the address of secondary startup into the
+ * system-wide flags register. The BootMonitor waits
+ * until it receives a soft interrupt, and then the
+ * secondary CPU branches to this address.
+ */
+ __raw_writel(virt_to_phys(zx_secondary_startup),
+ aonsysctrl_base + AON_SYS_CTRL_RESERVED1);
+
+ iounmap(aonsysctrl_base);
+ of_node_put(np);
+
+ np = of_find_compatible_node(NULL, NULL, "zte,zx296702-pcu");
+ pcu_base = of_iomap(np, 0);
+ of_node_put(np);
+ WARN_ON(!pcu_base);
+
+ np = of_find_compatible_node(NULL, NULL, "zte,zx-bus-matrix");
+ matrix_base = of_iomap(np, 0);
+ of_node_put(np);
+ WARN_ON(!matrix_base);
+
+ /* Map the first 4 KB IRAM for suspend usage */
+ sys_iram = __arm_ioremap_exec(ZX_IRAM_BASE, PAGE_SIZE, false);
+ zx_secondary_startup_pa = virt_to_phys(zx_secondary_startup);
+ fncpy(sys_iram, &zx_resume_jump, zx_suspend_iram_sz);
+}
+
+static int zx_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ static bool first_boot = true;
+
+ if (first_boot) {
+ arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+ first_boot = false;
+ return 0;
+ }
+
+ /* Swap the base address mapping between IRAM and IROM */
+ writel_relaxed(0x1, matrix_base + BUS_MATRIX_REMAP_CONFIG);
+
+ /* Power on CPU1 */
+ writel_relaxed(0x0, pcu_base + PCU_CPU1_CTRL);
+
+ /* Wait for power on ack */
+ while (readl_relaxed(pcu_base + PCU_CPU1_ST) & 0x4)
+ cpu_relax();
+
+ /* Swap back the mapping of IRAM and IROM */
+ writel_relaxed(0x0, matrix_base + BUS_MATRIX_REMAP_CONFIG);
+
+ return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static inline void cpu_enter_lowpower(void)
+{
+ unsigned int v;
+
+ asm volatile(
+ "mcr p15, 0, %1, c7, c5, 0\n"
+ " mcr p15, 0, %1, c7, c10, 4\n"
+ /*
+ * Turn off coherency
+ */
+ " mrc p15, 0, %0, c1, c0, 1\n"
+ " bic %0, %0, %3\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ " mrc p15, 0, %0, c1, c0, 0\n"
+ " bic %0, %0, %2\n"
+ " mcr p15, 0, %0, c1, c0, 0\n"
+ : "=&r" (v)
+ : "r" (0), "Ir" (CR_C), "Ir" (0x40)
+ : "cc");
+}
+
+static int zx_cpu_kill(unsigned int cpu)
+{
+ unsigned long timeout = jiffies + msecs_to_jiffies(2000);
+
+ writel_relaxed(0x2, pcu_base + PCU_CPU1_CTRL);
+
+ while ((readl_relaxed(pcu_base + PCU_CPU1_ST) & 0x3) != 0x0) {
+ if (time_after(jiffies, timeout)) {
+ pr_err("*** cpu1 poweroff timeout\n");
+ break;
+ }
+ }
+ return 1;
+}
+
+static void zx_cpu_die(unsigned int cpu)
+{
+ scu_power_mode(scu_base, SCU_PM_POWEROFF);
+ cpu_enter_lowpower();
+
+ while (1)
+ cpu_do_idle();
+}
+#endif
+
+static void zx_secondary_init(unsigned int cpu)
+{
+ scu_power_mode(scu_base, SCU_PM_NORMAL);
+}
+
+struct smp_operations zx_smp_ops __initdata = {
+ .smp_prepare_cpus = zx_smp_prepare_cpus,
+ .smp_secondary_init = zx_secondary_init,
+ .smp_boot_secondary = zx_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_kill = zx_cpu_kill,
+ .cpu_die = zx_cpu_die,
+#endif
+};
+
+CPU_METHOD_OF_DECLARE(zx_smp, "zte,zx296702-smp", &zx_smp_ops);
--
1.9.1