Merge tag 'tegra-for-3.7-cpu-hotplug' of git://git.kernel.org/pub/scm…

…/linux/kernel/git/swarren/linux-tegra into next/soc

From Stephen Warren:

ARM: tegra: implement CPU hotplug

This branch implements CPU hot-plugging support for both Tegra20 and
Tegra30. Portions of the implementation are contained in the clock
driver, hence this branch is based on the common clock conversion in
order to avoid duplicating work.

By Joseph Lo
via Stephen Warren
* tag 'tegra-for-3.7-cpu-hotplug' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra:
  ARM: tegra20: add CPU hotplug support
  ARM: tegra30: add CPU hotplug support
  ARM: tegra: clean up the common assembly macros into sleep.h
  ARM: tegra: replace the CPU CAR access code by tegra_cpu_car_ops
  ARM: tegra: introduce tegra_cpu_car_ops structures

arch/arm/mach-tegra/Makefile

@@ -15,8 +15,10 @@ obj-$(CONFIG_CPU_IDLE)			+= sleep.o
 obj-$(CONFIG_ARCH_TEGRA_2x_SOC)         += tegra20_clocks.o
 obj-$(CONFIG_ARCH_TEGRA_2x_SOC)         += tegra20_clocks_data.o
 obj-$(CONFIG_ARCH_TEGRA_2x_SOC)		+= tegra2_emc.o
+obj-$(CONFIG_ARCH_TEGRA_2x_SOC)		+= sleep-t20.o
 obj-$(CONFIG_ARCH_TEGRA_3x_SOC)		+= tegra30_clocks.o
 obj-$(CONFIG_ARCH_TEGRA_3x_SOC)		+= tegra30_clocks_data.o
+obj-$(CONFIG_ARCH_TEGRA_3x_SOC)		+= sleep-t30.o
 obj-$(CONFIG_SMP)			+= platsmp.o headsmp.o
 obj-$(CONFIG_SMP)                       += reset.o
 obj-$(CONFIG_HOTPLUG_CPU)               += hotplug.o

arch/arm/mach-tegra/clock.c

@@ -31,6 +31,10 @@
 
 #include "board.h"
 #include "clock.h"
+#include "tegra_cpu_car.h"
+
+/* Global data of Tegra CPU CAR ops */
+struct tegra_cpu_car_ops *tegra_cpu_car_ops;
 
 /*
  * Locking:

arch/arm/mach-tegra/common.c

@@ -34,6 +34,7 @@
 #include "fuse.h"
 #include "pmc.h"
 #include "apbio.h"
+#include "sleep.h"
 
 /*
  * Storage for debug-macro.S's state.
@@ -135,6 +136,7 @@ void __init tegra20_init_early(void)
 	tegra_init_cache(0x331, 0x441);
 	tegra_pmc_init();
 	tegra_powergate_init();
+	tegra20_hotplug_init();
 }
 #endif
 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
@@ -147,6 +149,7 @@ void __init tegra30_init_early(void)
 	tegra_init_cache(0x441, 0x551);
 	tegra_pmc_init();
 	tegra_powergate_init();
+	tegra30_hotplug_init();
 }
 #endif
 

arch/arm/mach-tegra/headsmp.S

@@ -7,17 +7,13 @@
 
 #include "flowctrl.h"
 #include "reset.h"
+#include "sleep.h"
 
 #define APB_MISC_GP_HIDREV	0x804
 #define PMC_SCRATCH41	0x140
 
 #define RESET_DATA(x)	((TEGRA_RESET_##x)*4)
 
-	.macro mov32, reg, val
-	movw	\reg, #:lower16:\val
-	movt	\reg, #:upper16:\val
-	.endm
-
         .section ".text.head", "ax"
 	__CPUINIT
 

arch/arm/mach-tegra/hotplug.c

@@ -1,91 +1,23 @@
 /*
- *  linux/arch/arm/mach-realview/hotplug.c
  *
  *  Copyright (C) 2002 ARM Ltd.
  *  All Rights Reserved
+ *  Copyright (c) 2010, 2012 NVIDIA Corporation. 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/cacheflush.h>
-#include <asm/cp15.h>
+#include <asm/smp_plat.h>
 
-static inline void cpu_enter_lowpower(void)
-{
-	unsigned int v;
-
-	flush_cache_all();
-	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");
+#include "sleep.h"
+#include "tegra_cpu_car.h"
 
-		/*if (pen_release == 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)++;
-	}
-}
+static void (*tegra_hotplug_shutdown)(void);
 
 int platform_cpu_kill(unsigned int cpu)
 {
@@ -99,22 +31,20 @@ int platform_cpu_kill(unsigned int cpu)
  */
 void platform_cpu_die(unsigned int cpu)
 {
-	int spurious = 0;
+	cpu = cpu_logical_map(cpu);
 
-	/*
-	 * we're ready for shutdown now, so do it
-	 */
-	cpu_enter_lowpower();
-	platform_do_lowpower(cpu, &spurious);
+	/* Flush the L1 data cache. */
+	flush_cache_all();
 
-	/*
-	 * bring this CPU back into the world of cache
-	 * coherency, and then restore interrupts
-	 */
-	cpu_leave_lowpower();
+	/* Shut down the current CPU. */
+	tegra_hotplug_shutdown();
 
-	if (spurious)
-		pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
+	/* Clock gate the CPU */
+	tegra_wait_cpu_in_reset(cpu);
+	tegra_disable_cpu_clock(cpu);
+
+	/* Should never return here. */
+	BUG();
 }
 
 int platform_cpu_disable(unsigned int cpu)
@@ -125,3 +55,19 @@ int platform_cpu_disable(unsigned int cpu)
 	 */
 	return cpu == 0 ? -EPERM : 0;
 }
+
+#ifdef CONFIG_ARCH_TEGRA_2x_SOC
+extern void tegra20_hotplug_shutdown(void);
+void __init tegra20_hotplug_init(void)
+{
+	tegra_hotplug_shutdown = tegra20_hotplug_shutdown;
+}
+#endif
+
+#ifdef CONFIG_ARCH_TEGRA_3x_SOC
+extern void tegra30_hotplug_shutdown(void);
+void __init tegra30_hotplug_init(void)
+{
+	tegra_hotplug_shutdown = tegra30_hotplug_shutdown;
+}
+#endif

arch/arm/mach-tegra/platsmp.c

@@ -31,24 +31,14 @@
 #include "fuse.h"
 #include "flowctrl.h"
 #include "reset.h"
+#include "tegra_cpu_car.h"
 
 extern void tegra_secondary_startup(void);
 
 static void __iomem *scu_base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE);
 
 #define EVP_CPU_RESET_VECTOR \
 	(IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE) + 0x100)
-#define CLK_RST_CONTROLLER_CLK_CPU_CMPLX \
-	(IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x4c)
-#define CLK_RST_CONTROLLER_RST_CPU_CMPLX_SET \
-	(IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x340)
-#define CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR \
-	(IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x344)
-#define CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR \
-	(IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x34c)
-
-#define CPU_CLOCK(cpu)	(0x1<<(8+cpu))
-#define CPU_RESET(cpu)	(0x1111ul<<(cpu))
 
 void __cpuinit platform_secondary_init(unsigned int cpu)
 {
@@ -63,13 +53,8 @@ void __cpuinit platform_secondary_init(unsigned int cpu)
 
 static int tegra20_power_up_cpu(unsigned int cpu)
 {
-	u32 reg;
-
 	/* Enable the CPU clock. */
-	reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
-	writel(reg & ~CPU_CLOCK(cpu), CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
-	barrier();
-	reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
+	tegra_enable_cpu_clock(cpu);
 
 	/* Clear flow controller CSR. */
 	flowctrl_write_cpu_csr(cpu, 0);
@@ -79,7 +64,6 @@ static int tegra20_power_up_cpu(unsigned int cpu)
 
 static int tegra30_power_up_cpu(unsigned int cpu)
 {
-	u32 reg;
 	int ret, pwrgateid;
 	unsigned long timeout;
 
@@ -103,8 +87,7 @@ static int tegra30_power_up_cpu(unsigned int cpu)
 	}
 
 	/* CPU partition is powered. Enable the CPU clock. */
-	writel(CPU_CLOCK(cpu), CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR);
-	reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR);
+	tegra_enable_cpu_clock(cpu);
 	udelay(10);
 
 	/* Remove I/O clamps. */
@@ -128,8 +111,7 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
 	 * via the flow controller). This will have no effect on first boot
 	 * of the CPU since it should already be in reset.
 	 */
-	writel(CPU_RESET(cpu), CLK_RST_CONTROLLER_RST_CPU_CMPLX_SET);
-	dmb();
+	tegra_put_cpu_in_reset(cpu);
 
 	/*
 	 * Unhalt the CPU. If the flow controller was used to power-gate the
@@ -155,8 +137,7 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
 		goto done;
 
 	/* Take the CPU out of reset. */
-	writel(CPU_RESET(cpu), CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR);
-	wmb();
+	tegra_cpu_out_of_reset(cpu);
 done:
 	return status;
 }

arch/arm/mach-tegra/sleep-t20.S

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2010-2012, NVIDIA Corporation. All rights reserved.
+ * Copyright (c) 2011, Google, Inc.
+ *
+ * Author: Colin Cross <ccross@android.com>
+ *         Gary King <gking@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/assembler.h>
+
+#include <mach/iomap.h>
+
+#include "sleep.h"
+#include "flowctrl.h"
+
+#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP)
+/*
+ * tegra20_hotplug_shutdown(void)
+ *
+ * puts the current cpu in reset
+ * should never return
+ */
+ENTRY(tegra20_hotplug_shutdown)
+	/* Turn off SMP coherency */
+	exit_smp r4, r5
+
+	/* Put this CPU down */
+	cpu_id	r0
+	bl	tegra20_cpu_shutdown
+	mov	pc, lr			@ should never get here
+ENDPROC(tegra20_hotplug_shutdown)
+
+/*
+ * tegra20_cpu_shutdown(int cpu)
+ *
+ * r0 is cpu to reset
+ *
+ * puts the specified CPU in wait-for-event mode on the flow controller
+ * and puts the CPU in reset
+ * can be called on the current cpu or another cpu
+ * if called on the current cpu, does not return
+ * MUST NOT BE CALLED FOR CPU 0.
+ *
+ * corrupts r0-r3, r12
+ */
+ENTRY(tegra20_cpu_shutdown)
+	cmp	r0, #0
+	moveq	pc, lr			@ must not be called for CPU 0
+
+	cpu_to_halt_reg r1, r0
+	ldr	r3, =TEGRA_FLOW_CTRL_VIRT
+	mov	r2, #FLOW_CTRL_WAITEVENT | FLOW_CTRL_JTAG_RESUME
+	str	r2, [r3, r1]		@ put flow controller in wait event mode
+	ldr	r2, [r3, r1]
+	isb
+	dsb
+	movw	r1, 0x1011
+	mov	r1, r1, lsl r0
+	ldr	r3, =TEGRA_CLK_RESET_VIRT
+	str	r1, [r3, #0x340]	@ put slave CPU in reset
+	isb
+	dsb
+	cpu_id	r3
+	cmp	r3, r0
+	beq	.
+	mov	pc, lr
+ENDPROC(tegra20_cpu_shutdown)
+#endif