Merge tag 'oxnas-arm-soc-for-4.10-v2' of https://github.com/OXNAS/linux into next/soc

Pull "ARM: OXNAS SoC updates for 4.10" from Neil Armstrong:

- Add SMP support for the Oxford Semiconductor OX820 SoC
from http://lkml.kernel.org/r/20161021085848.1754-1-narmstrong@baylibre.com

Changes since v1 Pull Request at : http://lkml.kernel.org/r/1305c61f-b1ef-7caf-7788-67e2b907e873@baylibre.com
 - Clarify copyright dates in commit message
 - Remove linux/arch/... lines from the top of the files

* tag 'oxnas-arm-soc-for-4.10-v2' of https://github.com/OXNAS/linux:
  ARM: oxnas: Add OX820 config and makefile entry
  ARM: oxnas: Add OX820 SMP support

arch/arm/Makefile

@@ -191,6 +191,7 @@ machine-$(CONFIG_ARCH_MXS)		+= mxs
 machine-$(CONFIG_ARCH_NETX)		+= netx
 machine-$(CONFIG_ARCH_NOMADIK)		+= nomadik
 machine-$(CONFIG_ARCH_NSPIRE)		+= nspire
+machine-$(CONFIG_ARCH_OXNAS)		+= oxnas
 machine-$(CONFIG_ARCH_OMAP1)		+= omap1
 machine-$(CONFIG_ARCH_OMAP2PLUS)	+= omap2
 machine-$(CONFIG_ARCH_ORION5X)		+= orion5x

arch/arm/mach-oxnas/Kconfig

 menuconfig ARCH_OXNAS
 	bool "Oxford Semiconductor OXNAS Family SoCs"
 	select ARCH_HAS_RESET_CONTROLLER
+	select COMMON_CLK_OXNAS
 	select GPIOLIB
+	select MFD_SYSCON
+	select OXNAS_RPS_TIMER
+	select PINCTRL_OXNAS
+	select RESET_CONTROLLER
+	select RESET_OXNAS
+	select VERSATILE_FPGA_IRQ
 	select PINCTRL
-	depends on ARCH_MULTI_V5
+	depends on ARCH_MULTI_V5 || ARCH_MULTI_V6
 	help
 	  Support for OxNas SoC family developed by Oxford Semiconductor.
 
@@ -11,16 +18,21 @@ if ARCH_OXNAS
 
 config MACH_OX810SE
 	bool "Support OX810SE Based Products"
-	select ARCH_HAS_RESET_CONTROLLER
-	select COMMON_CLK_OXNAS
+	depends on ARCH_MULTI_V5
 	select CPU_ARM926T
-	select MFD_SYSCON
-	select OXNAS_RPS_TIMER
-	select PINCTRL_OXNAS
-	select RESET_CONTROLLER
-	select RESET_OXNAS
-	select VERSATILE_FPGA_IRQ
 	help
 	  Include Support for the Oxford Semiconductor OX810SE SoC Based Products.
 
+config MACH_OX820
+	bool "Support OX820 Based Products"
+	depends on ARCH_MULTI_V6
+	select ARM_GIC
+	select DMA_CACHE_RWFO if SMP
+	select CPU_V6K
+	select HAVE_SMP
+	select HAVE_ARM_SCU if SMP
+	select HAVE_ARM_TWD if SMP
+	help
+	  Include Support for the Oxford Semiconductor OX820 SoC Based Products.
+
 endif

arch/arm/mach-oxnas/Makefile

+obj-$(CONFIG_SMP)		+= platsmp.o headsmp.o
+obj-$(CONFIG_HOTPLUG_CPU) 	+= hotplug.o

arch/arm/mach-oxnas/headsmp.S

+/*
+ * Copyright (C) 2013 Ma Haijun <mahaijuns@gmail.com>
+ * Copyright (c) 2003 ARM Limited
+ * 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/linkage.h>
+#include <linux/init.h>
+
+	__INIT
+
+/*
+ * OX820 specific entry point for secondary CPUs.
+ */
+ENTRY(ox820_secondary_startup)
+	mov r4, #0
+	/* invalidate both caches and branch target cache */
+	mcr p15, 0, r4, c7, c7, 0
+	/*
+	 * we've been released from the holding pen: secondary_stack
+	 * should now contain the SVC stack for this core
+	 */
+	b	secondary_startup

arch/arm/mach-oxnas/hotplug.c

+/*
+ *  Copyright (C) 2002 ARM Ltd.
+ *  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/kernel.h>
+#include <linux/errno.h>
+#include <linux/smp.h>
+
+#include <asm/cp15.h>
+#include <asm/smp_plat.h>
+
+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, #0x20\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)
+	  : "cc");
+}
+
+static inline void cpu_leave_lowpower(void)
+{
+	unsigned int v;
+
+	asm volatile(	"mrc	p15, 0, %0, c1, c0, 0\n"
+	"	orr	%0, %0, %1\n"
+	"	mcr	p15, 0, %0, c1, c0, 0\n"
+	"	mrc	p15, 0, %0, c1, c0, 1\n"
+	"	orr	%0, %0, #0x20\n"
+	"	mcr	p15, 0, %0, c1, c0, 1\n"
+	  : "=&r" (v)
+	  : "Ir" (CR_C)
+	  : "cc");
+}
+
+static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
+{
+	/*
+	 * there is no power-control hardware on this platform, so all
+	 * we can do is put the core into WFI; this is safe as the calling
+	 * code will have already disabled interrupts
+	 */
+	for (;;) {
+		/*
+		 * here's the WFI
+		 */
+		asm(".word	0xe320f003\n"
+		    :
+		    :
+		    : "memory", "cc");
+
+		if (pen_release == cpu_logical_map(cpu)) {
+			/*
+			 * OK, proper wakeup, we're done
+			 */
+			break;
+		}
+
+		/*
+		 * Getting here, means that we have come out of WFI without
+		 * having been woken up - this shouldn't happen
+		 *
+		 * Just note it happening - when we're woken, we can report
+		 * its occurrence.
+		 */
+		(*spurious)++;
+	}
+}
+
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+void ox820_cpu_die(unsigned int cpu)
+{
+	int spurious = 0;
+
+	/*
+	 * we're ready for shutdown now, so do it
+	 */
+	cpu_enter_lowpower();
+	platform_do_lowpower(cpu, &spurious);
+
+	/*
+	 * bring this CPU back into the world of cache
+	 * coherency, and then restore interrupts
+	 */
+	cpu_leave_lowpower();
+
+	if (spurious)
+		pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
+}

arch/arm/mach-oxnas/platsmp.c

+/*
+ * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2013 Ma Haijun <mahaijuns@gmail.com>
+ * Copyright (C) 2002 ARM Ltd.
+ * 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/io.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/smp_plat.h>
+#include <asm/smp_scu.h>
+
+extern void ox820_secondary_startup(void);
+extern void ox820_cpu_die(unsigned int cpu);
+
+static void __iomem *cpu_ctrl;
+static void __iomem *gic_cpu_ctrl;
+
+#define HOLDINGPEN_CPU_OFFSET		0xc8
+#define HOLDINGPEN_LOCATION_OFFSET	0xc4
+
+#define GIC_NCPU_OFFSET(cpu)		(0x100 + (cpu)*0x100)
+#define GIC_CPU_CTRL			0x00
+#define GIC_CPU_CTRL_ENABLE		1
+
+int __init ox820_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	/*
+	 * 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.
+	 */
+	writel(virt_to_phys(ox820_secondary_startup),
+			cpu_ctrl + HOLDINGPEN_LOCATION_OFFSET);
+
+	writel(cpu, cpu_ctrl + HOLDINGPEN_CPU_OFFSET);
+
+	/*
+	 * Enable GIC cpu interface in CPU Interface Control Register
+	 */
+	writel(GIC_CPU_CTRL_ENABLE,
+		gic_cpu_ctrl + GIC_NCPU_OFFSET(cpu) + GIC_CPU_CTRL);
+
+	/*
+	 * Send the secondary CPU a soft interrupt, thereby causing
+	 * the boot monitor to read the system wide flags register,
+	 * and branch to the address found there.
+	 */
+	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+
+	return 0;
+}
+
+static void __init ox820_smp_prepare_cpus(unsigned int max_cpus)
+{
+	struct device_node *np;
+	void __iomem *scu_base;
+
+	np = of_find_compatible_node(NULL, NULL, "arm,arm11mp-scu");
+	scu_base = of_iomap(np, 0);
+	of_node_put(np);
+	if (!scu_base)
+		return;
+
+	/* Remap CPU Interrupt Interface Registers */
+	np = of_find_compatible_node(NULL, NULL, "arm,arm11mp-gic");
+	gic_cpu_ctrl = of_iomap(np, 1);
+	of_node_put(np);
+	if (!gic_cpu_ctrl)
+		goto unmap_scu;
+
+	np = of_find_compatible_node(NULL, NULL, "oxsemi,ox820-sys-ctrl");
+	cpu_ctrl = of_iomap(np, 0);
+	of_node_put(np);
+	if (!cpu_ctrl)
+		goto unmap_scu;
+
+	scu_enable(scu_base);
+	flush_cache_all();
+
+unmap_scu:
+	iounmap(scu_base);
+}
+
+static const struct smp_operations ox820_smp_ops __initconst = {
+	.smp_prepare_cpus	= ox820_smp_prepare_cpus,
+	.smp_boot_secondary	= ox820_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+	.cpu_die		= ox820_cpu_die,
+#endif
+};
+
+CPU_METHOD_OF_DECLARE(ox820_smp, "oxsemi,ox820-smp", &ox820_smp_ops);