]> git.karo-electronics.de Git - linux-beck.git/commitdiff
ARM: Alpine: smp support
authorTsahee Zidenberg <tsahee@annapurnalabs.com>
Thu, 12 Mar 2015 11:53:06 +0000 (13:53 +0200)
committerArnd Bergmann <arnd@arndb.de>
Mon, 16 Mar 2015 14:24:12 +0000 (15:24 +0100)
This patch introduces support for waking up secondary CPU cores on
Alpine platform.

Signed-off-by: Barak Wasserstrom <barak@annapurnalabs.com>
Signed-off-by: Tsahee Zidenberg <tsahee@annapurnalabs.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
arch/arm/mach-alpine/Kconfig
arch/arm/mach-alpine/Makefile
arch/arm/mach-alpine/alpine_cpu_pm.c [new file with mode: 0644]
arch/arm/mach-alpine/alpine_cpu_pm.h [new file with mode: 0644]
arch/arm/mach-alpine/alpine_cpu_resume.h [new file with mode: 0644]
arch/arm/mach-alpine/platsmp.c [new file with mode: 0644]

index 44b9a8f4e5bbabeb106edabb5e4bf36766917031..79b26491a96c655a937dd40abb769c30dc1878b8 100644 (file)
@@ -4,5 +4,7 @@ config ARCH_ALPINE
        select ARM_GIC
        select GENERIC_IRQ_CHIP
        select HAVE_ARM_ARCH_TIMER
+       select HAVE_SMP
+       select MFD_SYSCON
        help
          This enables support for the Annapurna Labs Alpine V1 boards.
index b7dbb12d89cd6317b3c92c8574148cd3e3e938c1..b6674890be7134823d2d63b88dc50698fed0daf2 100644 (file)
@@ -1 +1,2 @@
 obj-y                          += alpine_machine.o
+obj-$(CONFIG_SMP)              += platsmp.o alpine_cpu_pm.o
diff --git a/arch/arm/mach-alpine/alpine_cpu_pm.c b/arch/arm/mach-alpine/alpine_cpu_pm.c
new file mode 100644 (file)
index 0000000..121c77c
--- /dev/null
@@ -0,0 +1,70 @@
+/*
+ * Low-level power-management support for Alpine platform.
+ *
+ * Copyright (C) 2015 Annapurna Labs Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#include "alpine_cpu_pm.h"
+#include "alpine_cpu_resume.h"
+
+/* NB registers */
+#define AL_SYSFAB_POWER_CONTROL(cpu)   (0x2000 + (cpu)*0x100 + 0x20)
+
+static struct regmap *al_sysfabric;
+static struct al_cpu_resume_regs __iomem *al_cpu_resume_regs;
+static int wakeup_supported;
+
+int alpine_cpu_wakeup(unsigned int phys_cpu, uint32_t phys_resume_addr)
+{
+       if (!wakeup_supported)
+               return -ENOSYS;
+
+       /*
+        * Set CPU resume address -
+        * secure firmware running on boot will jump to this address
+        * after setting proper CPU mode, and initialiing e.g. secure
+        * regs (the same mode all CPUs are booted to - usually HYP)
+        */
+       writel(phys_resume_addr,
+              &al_cpu_resume_regs->per_cpu[phys_cpu].resume_addr);
+
+       /* Power-up the CPU */
+       regmap_write(al_sysfabric, AL_SYSFAB_POWER_CONTROL(phys_cpu), 0);
+
+       return 0;
+}
+
+void __init alpine_cpu_pm_init(void)
+{
+       struct device_node *np;
+       uint32_t watermark;
+
+       al_sysfabric = syscon_regmap_lookup_by_compatible("al,alpine-sysfabric-service");
+
+       np = of_find_compatible_node(NULL, NULL, "al,alpine-cpu-resume");
+       al_cpu_resume_regs = of_iomap(np, 0);
+
+       wakeup_supported = !IS_ERR(al_sysfabric) && al_cpu_resume_regs;
+
+       if (wakeup_supported) {
+               watermark = readl(&al_cpu_resume_regs->watermark);
+               wakeup_supported = (watermark & AL_CPU_RESUME_MAGIC_NUM_MASK)
+                                   == AL_CPU_RESUME_MAGIC_NUM;
+       }
+}
diff --git a/arch/arm/mach-alpine/alpine_cpu_pm.h b/arch/arm/mach-alpine/alpine_cpu_pm.h
new file mode 100644 (file)
index 0000000..5179e69
--- /dev/null
@@ -0,0 +1,26 @@
+/*
+ * Low-level power-management support for Alpine platform.
+ *
+ * Copyright (C) 2015 Annapurna Labs Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __ALPINE_CPU_PM_H__
+#define __ALPINE_CPU_PM_H__
+
+/* Alpine CPU Power Management Services Initialization */
+void alpine_cpu_pm_init(void);
+
+/* Wake-up a CPU */
+int alpine_cpu_wakeup(unsigned int phys_cpu, uint32_t phys_resume_addr);
+
+#endif /* __ALPINE_CPU_PM_H__ */
diff --git a/arch/arm/mach-alpine/alpine_cpu_resume.h b/arch/arm/mach-alpine/alpine_cpu_resume.h
new file mode 100644 (file)
index 0000000..c80150c
--- /dev/null
@@ -0,0 +1,38 @@
+/*
+ * Annapurna labs cpu-resume register structure.
+ *
+ * Copyright (C) 2015 Annapurna Labs Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef ALPINE_CPU_RESUME_H_
+#define ALPINE_CPU_RESUME_H_
+
+/* Per-cpu regs */
+struct al_cpu_resume_regs_per_cpu {
+       uint32_t        flags;
+       uint32_t        resume_addr;
+};
+
+/* general regs */
+struct al_cpu_resume_regs {
+       /* Watermark for validating the CPU resume struct */
+       uint32_t watermark;
+       uint32_t flags;
+       struct al_cpu_resume_regs_per_cpu per_cpu[];
+};
+
+/* The expected magic number for validating the resume addresses */
+#define AL_CPU_RESUME_MAGIC_NUM                0xf0e1d200
+#define AL_CPU_RESUME_MAGIC_NUM_MASK   0xffffff00
+
+#endif /* ALPINE_CPU_RESUME_H_ */
diff --git a/arch/arm/mach-alpine/platsmp.c b/arch/arm/mach-alpine/platsmp.c
new file mode 100644 (file)
index 0000000..f78429f
--- /dev/null
@@ -0,0 +1,49 @@
+/*
+ * SMP operations for Alpine platform.
+ *
+ * Copyright (C) 2015 Annapurna Labs Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#include <asm/smp_plat.h>
+
+#include "alpine_cpu_pm.h"
+
+static int alpine_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+       phys_addr_t addr;
+
+       addr = virt_to_phys(secondary_startup);
+
+       if (addr > (phys_addr_t)(uint32_t)(-1)) {
+               pr_err("FAIL: resume address over 32bit (%pa)", &addr);
+               return -EINVAL;
+       }
+
+       return alpine_cpu_wakeup(cpu_logical_map(cpu), (uint32_t)addr);
+}
+
+static void __init alpine_smp_prepare_cpus(unsigned int max_cpus)
+{
+       alpine_cpu_pm_init();
+}
+
+static struct smp_operations alpine_smp_ops __initdata = {
+       .smp_prepare_cpus       = alpine_smp_prepare_cpus,
+       .smp_boot_secondary     = alpine_boot_secondary,
+};
+CPU_METHOD_OF_DECLARE(alpine_smp, "al,alpine-smp", &alpine_smp_ops);