Merge branch 'brcm/stb-smp-uart' into next/drivers

This resolves a nonobvious merge conflict that I got wrong the
first time.

* brcm/stb-smp-uart:
  bus: brcmstb_gisb: save and restore GISB timeout
  bus: brcmstb_gisb: register the fault code hook
  ARM: brcmstb: Kconfig: drop unneeded symbol selections
  ARM: brcmstb: reintroduce SMP support
  ARM: brcmstb: add debug UART for earlyprintk support

Conflicts:
	drivers/bus/brcmstb_gisb.c

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Florian Fainelli <f.fainelli@gmail.com>

7 files changed, 439 insertions, 10 deletions

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 03dc4c1a8736..6a4ee008b092 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -139,6 +139,17 @@ choice
 		  Say Y here if you want kernel low-level debugging support
 		  on Marvell Berlin SoC based platforms.
 
+	config DEBUG_BRCMSTB_UART
+		bool "Use BRCMSTB UART for low-level debug"
+		depends on ARCH_BRCMSTB
+		select DEBUG_UART_8250
+		help
+		  Say Y here if you want the debug print routines to direct
+		  their output to the first serial port on these devices.
+
+		  If you have a Broadcom STB chip and would like early print
+		  messages to appear over the UART, select this option.
+
 	config DEBUG_CLPS711X_UART1
 		bool "Kernel low-level debugging messages via UART1"
 		depends on ARCH_CLPS711X
@@ -1153,6 +1164,7 @@ config DEBUG_UART_PHYS
 	default 0xe0000000 if ARCH_SPEAR13XX
 	default 0xe4007000 if DEBUG_HIP04_UART
 	default 0xf0000be0 if ARCH_EBSA110
+	default 0xf040ab00 if DEBUG_BRCMSTB_UART
 	default 0xf1012000 if DEBUG_MVEBU_UART_ALTERNATE
 	default 0xf1012000 if ARCH_DOVE || ARCH_MV78XX0 || \
 				ARCH_ORION5X
@@ -1204,6 +1216,7 @@ config DEBUG_UART_VIRT
 	default 0xfb002000 if DEBUG_CNS3XXX
 	default 0xfb009000 if DEBUG_REALVIEW_STD_PORT
 	default 0xfb10c000 if DEBUG_REALVIEW_PB1176_PORT
+	default 0xfc40ab00 if DEBUG_BRCMSTB_UART
 	default 0xfcfe8600 if DEBUG_UART_BCM63XX
 	default 0xfd000000 if ARCH_SPEAR3XX || ARCH_SPEAR6XX
 	default 0xfd000000 if ARCH_SPEAR13XX
@@ -1260,7 +1273,8 @@ config DEBUG_UART_8250_WORD
 		ARCH_KEYSTONE || \
 		DEBUG_DAVINCI_DMx_UART0 || DEBUG_DAVINCI_DA8XX_UART1 || \
 		DEBUG_DAVINCI_DA8XX_UART2 || \
-		DEBUG_BCM_KONA_UART || DEBUG_RK32_UART2
+		DEBUG_BCM_KONA_UART || DEBUG_RK32_UART2 || \
+		DEBUG_BRCMSTB_UART
 
 config DEBUG_UART_8250_FLOW_CONTROL
 	bool "Enable flow control for 8250 UART"
diff --git a/arch/arm/mach-bcm/Kconfig b/arch/arm/mach-bcm/Kconfig
index 2abad742516d..9625dddb5cd3 100644
--- a/arch/arm/mach-bcm/Kconfig
+++ b/arch/arm/mach-bcm/Kconfig
@@ -118,10 +118,7 @@ config ARCH_BCM_63XX
 
 config ARCH_BRCMSTB
 	bool "Broadcom BCM7XXX based boards" if ARCH_MULTI_V7
-	depends on MMU
 	select ARM_GIC
-	select MIGHT_HAVE_PCI
-	select HAVE_SMP
 	select HAVE_ARM_ARCH_TIMER
 	select BRCMSTB_GISB_ARB
 	select BRCMSTB_L2_IRQ
diff --git a/arch/arm/mach-bcm/Makefile b/arch/arm/mach-bcm/Makefile
index 300ae4b79ae6..6710ea321220 100644
--- a/arch/arm/mach-bcm/Makefile
+++ b/arch/arm/mach-bcm/Makefile
@@ -38,5 +38,7 @@ obj-$(CONFIG_ARCH_BCM_5301X)	+= bcm_5301x.o
 obj-$(CONFIG_ARCH_BCM_63XX)	:= bcm63xx.o
 
 ifeq ($(CONFIG_ARCH_BRCMSTB),y)
+CFLAGS_platsmp-brcmstb.o	+= -march=armv7-a
 obj-y				+= brcmstb.o
+obj-$(CONFIG_SMP)		+= headsmp-brcmstb.o platsmp-brcmstb.o
 endif
diff --git a/arch/arm/mach-bcm/brcmstb.h b/arch/arm/mach-bcm/brcmstb.h
new file mode 100644
index 000000000000..ec0c3d112b36
--- /dev/null
+++ b/arch/arm/mach-bcm/brcmstb.h
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2013-2014 Broadcom Corporation
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __BRCMSTB_H__
+#define __BRCMSTB_H__
+
+void brcmstb_secondary_startup(void);
+
+#endif /* __BRCMSTB_H__ */
diff --git a/arch/arm/mach-bcm/headsmp-brcmstb.S b/arch/arm/mach-bcm/headsmp-brcmstb.S
new file mode 100644
index 000000000000..199c1ea58248
--- /dev/null
+++ b/arch/arm/mach-bcm/headsmp-brcmstb.S
@@ -0,0 +1,33 @@
+/*
+ * SMP boot code for secondary CPUs
+ * Based on arch/arm/mach-tegra/headsmp.S
+ *
+ * Copyright (C) 2010 NVIDIA, Inc.
+ * Copyright (C) 2013-2014 Broadcom Corporation
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <asm/assembler.h>
+#include <linux/linkage.h>
+#include <linux/init.h>
+
+        .section ".text.head", "ax"
+
+ENTRY(brcmstb_secondary_startup)
+        /*
+         * Ensure CPU is in a sane state by disabling all IRQs and switching
+         * into SVC mode.
+         */
+        setmode	PSR_I_BIT | PSR_F_BIT | SVC_MODE, r0
+
+        bl      v7_invalidate_l1
+        b       secondary_startup
+ENDPROC(brcmstb_secondary_startup)
diff --git a/arch/arm/mach-bcm/platsmp-brcmstb.c b/arch/arm/mach-bcm/platsmp-brcmstb.c
new file mode 100644
index 000000000000..31c87a284a34
--- /dev/null
+++ b/arch/arm/mach-bcm/platsmp-brcmstb.c
@@ -0,0 +1,329 @@
+/*
+ * Broadcom STB CPU SMP and hotplug support for ARM
+ *
+ * Copyright (C) 2013-2014 Broadcom Corporation
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/printk.h>
+#include <linux/regmap.h>
+#include <linux/smp.h>
+#include <linux/mfd/syscon.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/mach-types.h>
+#include <asm/smp_plat.h>
+
+#include "brcmstb.h"
+
+enum {
+	ZONE_MAN_CLKEN_MASK		= BIT(0),
+	ZONE_MAN_RESET_CNTL_MASK	= BIT(1),
+	ZONE_MAN_MEM_PWR_MASK		= BIT(4),
+	ZONE_RESERVED_1_MASK		= BIT(5),
+	ZONE_MAN_ISO_CNTL_MASK		= BIT(6),
+	ZONE_MANUAL_CONTROL_MASK	= BIT(7),
+	ZONE_PWR_DN_REQ_MASK		= BIT(9),
+	ZONE_PWR_UP_REQ_MASK		= BIT(10),
+	ZONE_BLK_RST_ASSERT_MASK	= BIT(12),
+	ZONE_PWR_OFF_STATE_MASK		= BIT(25),
+	ZONE_PWR_ON_STATE_MASK		= BIT(26),
+	ZONE_DPG_PWR_STATE_MASK		= BIT(28),
+	ZONE_MEM_PWR_STATE_MASK		= BIT(29),
+	ZONE_RESET_STATE_MASK		= BIT(31),
+	CPU0_PWR_ZONE_CTRL_REG		= 1,
+	CPU_RESET_CONFIG_REG		= 2,
+};
+
+static void __iomem *cpubiuctrl_block;
+static void __iomem *hif_cont_block;
+static u32 cpu0_pwr_zone_ctrl_reg;
+static u32 cpu_rst_cfg_reg;
+static u32 hif_cont_reg;
+
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * We must quiesce a dying CPU before it can be killed by the boot CPU. Because
+ * one or more cache may be disabled, we must flush to ensure coherency. We
+ * cannot use traditionl completion structures or spinlocks as they rely on
+ * coherency.
+ */
+static DEFINE_PER_CPU_ALIGNED(int, per_cpu_sw_state);
+
+static int per_cpu_sw_state_rd(u32 cpu)
+{
+	sync_cache_r(SHIFT_PERCPU_PTR(&per_cpu_sw_state, per_cpu_offset(cpu)));
+	return per_cpu(per_cpu_sw_state, cpu);
+}
+
+static void per_cpu_sw_state_wr(u32 cpu, int val)
+{
+	dmb();
+	per_cpu(per_cpu_sw_state, cpu) = val;
+	sync_cache_w(SHIFT_PERCPU_PTR(&per_cpu_sw_state, per_cpu_offset(cpu)));
+}
+#else
+static inline void per_cpu_sw_state_wr(u32 cpu, int val) { }
+#endif
+
+static void __iomem *pwr_ctrl_get_base(u32 cpu)
+{
+	void __iomem *base = cpubiuctrl_block + cpu0_pwr_zone_ctrl_reg;
+	base += (cpu_logical_map(cpu) * 4);
+	return base;
+}
+
+static u32 pwr_ctrl_rd(u32 cpu)
+{
+	void __iomem *base = pwr_ctrl_get_base(cpu);
+	return readl_relaxed(base);
+}
+
+static void pwr_ctrl_wr(u32 cpu, u32 val)
+{
+	void __iomem *base = pwr_ctrl_get_base(cpu);
+	writel(val, base);
+}
+
+static void cpu_rst_cfg_set(u32 cpu, int set)
+{
+	u32 val;
+	val = readl_relaxed(cpubiuctrl_block + cpu_rst_cfg_reg);
+	if (set)
+		val |= BIT(cpu_logical_map(cpu));
+	else
+		val &= ~BIT(cpu_logical_map(cpu));
+	writel_relaxed(val, cpubiuctrl_block + cpu_rst_cfg_reg);
+}
+
+static void cpu_set_boot_addr(u32 cpu, unsigned long boot_addr)
+{
+	const int reg_ofs = cpu_logical_map(cpu) * 8;
+	writel_relaxed(0, hif_cont_block + hif_cont_reg + reg_ofs);
+	writel_relaxed(boot_addr, hif_cont_block + hif_cont_reg + 4 + reg_ofs);
+}
+
+static void brcmstb_cpu_boot(u32 cpu)
+{
+	/* Mark this CPU as "up" */
+	per_cpu_sw_state_wr(cpu, 1);
+
+	/*
+	 * Set the reset vector to point to the secondary_startup
+	 * routine
+	 */
+	cpu_set_boot_addr(cpu, virt_to_phys(brcmstb_secondary_startup));
+
+	/* Unhalt the cpu */
+	cpu_rst_cfg_set(cpu, 0);
+}
+
+static void brcmstb_cpu_power_on(u32 cpu)
+{
+	/*
+	 * The secondary cores power was cut, so we must go through
+	 * power-on initialization.
+	 */
+	u32 tmp;
+
+	/* Request zone power up */
+	pwr_ctrl_wr(cpu, ZONE_PWR_UP_REQ_MASK);
+
+	/* Wait for the power up FSM to complete */
+	do {
+		tmp = pwr_ctrl_rd(cpu);
+	} while (!(tmp & ZONE_PWR_ON_STATE_MASK));
+}
+
+static int brcmstb_cpu_get_power_state(u32 cpu)
+{
+	int tmp = pwr_ctrl_rd(cpu);
+	return (tmp & ZONE_RESET_STATE_MASK) ? 0 : 1;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static void brcmstb_cpu_die(u32 cpu)
+{
+	v7_exit_coherency_flush(all);
+
+	per_cpu_sw_state_wr(cpu, 0);
+
+	/* Sit and wait to die */
+	wfi();
+
+	/* We should never get here... */
+	while (1)
+		;
+}
+
+static int brcmstb_cpu_kill(u32 cpu)
+{
+	u32 tmp;
+
+	while (per_cpu_sw_state_rd(cpu))
+		;
+
+	/* Program zone reset */
+	pwr_ctrl_wr(cpu, ZONE_RESET_STATE_MASK | ZONE_BLK_RST_ASSERT_MASK |
+			      ZONE_PWR_DN_REQ_MASK);
+
+	/* Verify zone reset */
+	tmp = pwr_ctrl_rd(cpu);
+	if (!(tmp & ZONE_RESET_STATE_MASK))
+		pr_err("%s: Zone reset bit for CPU %d not asserted!\n",
+			__func__, cpu);
+
+	/* Wait for power down */
+	do {
+		tmp = pwr_ctrl_rd(cpu);
+	} while (!(tmp & ZONE_PWR_OFF_STATE_MASK));
+
+	/* Flush pipeline before resetting CPU */
+	mb();
+
+	/* Assert reset on the CPU */
+	cpu_rst_cfg_set(cpu, 1);
+
+	return 1;
+}
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
+static int __init setup_hifcpubiuctrl_regs(struct device_node *np)
+{
+	int rc = 0;
+	char *name;
+	struct device_node *syscon_np = NULL;
+
+	name = "syscon-cpu";
+
+	syscon_np = of_parse_phandle(np, name, 0);
+	if (!syscon_np) {
+		pr_err("can't find phandle %s\n", name);
+		rc = -EINVAL;
+		goto cleanup;
+	}
+
+	cpubiuctrl_block = of_iomap(syscon_np, 0);
+	if (!cpubiuctrl_block) {
+		pr_err("iomap failed for cpubiuctrl_block\n");
+		rc = -EINVAL;
+		goto cleanup;
+	}
+
+	rc = of_property_read_u32_index(np, name, CPU0_PWR_ZONE_CTRL_REG,
+					&cpu0_pwr_zone_ctrl_reg);
+	if (rc) {
+		pr_err("failed to read 1st entry from %s property (%d)\n", name,
+			rc);
+		rc = -EINVAL;
+		goto cleanup;
+	}
+
+	rc = of_property_read_u32_index(np, name, CPU_RESET_CONFIG_REG,
+					&cpu_rst_cfg_reg);
+	if (rc) {
+		pr_err("failed to read 2nd entry from %s property (%d)\n", name,
+			rc);
+		rc = -EINVAL;
+		goto cleanup;
+	}
+
+cleanup:
+	of_node_put(syscon_np);
+	return rc;
+}
+
+static int __init setup_hifcont_regs(struct device_node *np)
+{
+	int rc = 0;
+	char *name;
+	struct device_node *syscon_np = NULL;
+
+	name = "syscon-cont";
+
+	syscon_np = of_parse_phandle(np, name, 0);
+	if (!syscon_np) {
+		pr_err("can't find phandle %s\n", name);
+		rc = -EINVAL;
+		goto cleanup;
+	}
+
+	hif_cont_block = of_iomap(syscon_np, 0);
+	if (!hif_cont_block) {
+		pr_err("iomap failed for hif_cont_block\n");
+		rc = -EINVAL;
+		goto cleanup;
+	}
+
+	/* Offset is at top of hif_cont_block */
+	hif_cont_reg = 0;
+
+cleanup:
+	of_node_put(syscon_np);
+	return rc;
+}
+
+static void __init brcmstb_cpu_ctrl_setup(unsigned int max_cpus)
+{
+	int rc;
+	struct device_node *np;
+	char *name;
+
+	name = "brcm,brcmstb-smpboot";
+	np = of_find_compatible_node(NULL, NULL, name);
+	if (!np) {
+		pr_err("can't find compatible node %s\n", name);
+		return;
+	}
+
+	rc = setup_hifcpubiuctrl_regs(np);
+	if (rc)
+		return;
+
+	rc = setup_hifcont_regs(np);
+	if (rc)
+		return;
+}
+
+static int brcmstb_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	/* Missing the brcm,brcmstb-smpboot DT node? */
+	if (!cpubiuctrl_block || !hif_cont_block)
+		return -ENODEV;
+
+	/* Bring up power to the core if necessary */
+	if (brcmstb_cpu_get_power_state(cpu) == 0)
+		brcmstb_cpu_power_on(cpu);
+
+	brcmstb_cpu_boot(cpu);
+
+	return 0;
+}
+
+static struct smp_operations brcmstb_smp_ops __initdata = {
+	.smp_prepare_cpus	= brcmstb_cpu_ctrl_setup,
+	.smp_boot_secondary	= brcmstb_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+	.cpu_kill		= brcmstb_cpu_kill,
+	.cpu_die		= brcmstb_cpu_die,
+#endif
+};
+
+CPU_METHOD_OF_DECLARE(brcmstb_smp, "brcm,brahma-b15", &brcmstb_smp_ops);
diff --git a/drivers/bus/brcmstb_gisb.c b/drivers/bus/brcmstb_gisb.c
index bfd40f11e921..46de8dc39eb4 100644
--- a/drivers/bus/brcmstb_gisb.c
+++ b/drivers/bus/brcmstb_gisb.c
@@ -23,6 +23,7 @@
 #include <linux/list.h>
 #include <linux/of.h>
 #include <linux/bitops.h>
+#include <linux/pm.h>
 
 #ifdef CONFIG_ARM
 #include <asm/bug.h>
@@ -94,6 +95,7 @@ struct brcmstb_gisb_arb_device {
 	struct list_head next;
 	u32 valid_mask;
 	const char *master_names[sizeof(u32) * BITS_PER_BYTE];
+	u32 saved_timeout;
 };
 
 static LIST_HEAD(brcmstb_gisb_arb_device_list);
@@ -226,12 +228,6 @@ static int brcmstb_bus_error_handler(unsigned long addr, unsigned int fsr,
 
 	return ret;
 }
-
-void __init brcmstb_hook_fault_code(void)
-{
-	hook_fault_code(22, brcmstb_bus_error_handler, SIGBUS, 0,
-			"imprecise external abort");
-}
 #endif
 
 static irqreturn_t brcmstb_gisb_timeout_handler(int irq, void *dev_id)
@@ -346,17 +342,56 @@ static int __init brcmstb_gisb_arb_probe(struct platform_device *pdev)
 
 	list_add_tail(&gdev->next, &brcmstb_gisb_arb_device_list);
 
+#ifdef CONFIG_ARM
+	hook_fault_code(22, brcmstb_bus_error_handler, SIGBUS, 0,
+			"imprecise external abort");
+#endif
+
 	dev_info(&pdev->dev, "registered mem: %p, irqs: %d, %d\n",
 			gdev->base, timeout_irq, tea_irq);
 
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int brcmstb_gisb_arb_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct brcmstb_gisb_arb_device *gdev = platform_get_drvdata(pdev);
+
+	gdev->saved_timeout = gisb_read(gdev, ARB_TIMER);
+
+	return 0;
+}
+
+/* Make sure we provide the same timeout value that was configured before, and
+ * do this before the GISB timeout interrupt handler has any chance to run.
+ */
+static int brcmstb_gisb_arb_resume_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct brcmstb_gisb_arb_device *gdev = platform_get_drvdata(pdev);
+
+	gisb_write(gdev, gdev->saved_timeout, ARB_TIMER);
+
+	return 0;
+}
+#else
+#define brcmstb_gisb_arb_suspend       NULL
+#define brcmstb_gisb_arb_resume_noirq  NULL
+#endif
+
+static const struct dev_pm_ops brcmstb_gisb_arb_pm_ops = {
+	.suspend	= brcmstb_gisb_arb_suspend,
+	.resume_noirq	= brcmstb_gisb_arb_resume_noirq,
+};
+
 static struct platform_driver brcmstb_gisb_arb_driver = {
 	.driver = {
 		.name	= "brcm-gisb-arb",
 		.owner	= THIS_MODULE,
 		.of_match_table = brcmstb_gisb_arb_of_match,
+		.pm	= &brcmstb_gisb_arb_pm_ops,
 	},
 };