arch/arm/mach-omap2/omap-smp.c - kernel/bruno - Git at Google

 /*
  * OMAP4 SMP source file. It contains platform specific functions
  * needed for the linux smp kernel.
  *
  * Copyright (C) 2009 Texas Instruments, Inc.
  *
  * Author:
  *      Santosh Shilimkar <santosh.shilimkar@ti.com>
  *
  * Platform file needed for the OMAP4 SMP. This file is based on arm
  * realview smp platform.
  * * Copyright (c) 2002 ARM Limited.
  *
  * 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/init.h>
 #include <linux/device.h>
 #include <linux/smp.h>
 #include <linux/io.h>
 #include <linux/irqchip/arm-gic.h>

 #include <asm/smp_scu.h>
 #include <asm/virt.h>

 #include "omap-secure.h"
 #include "omap-wakeupgen.h"
 #include <asm/cputype.h>

 #include "soc.h"
 #include "iomap.h"
 #include "common.h"
 #include "clockdomain.h"
 #include "pm.h"

 #define CPU_MASK		0xff0ffff0
 #define CPU_CORTEX_A9		0x410FC090
 #define CPU_CORTEX_A15		0x410FC0F0

 #define OMAP5_CORE_COUNT	0x2

 /* SCU base address */
 static void __iomem *scu_base;

 static DEFINE_SPINLOCK(boot_lock);

 void __iomem *omap4_get_scu_base(void)
 {
 	return scu_base;
 }

 static void omap4_secondary_init(unsigned int cpu)
 {
 	/*
 	 * Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
 	 * OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
 	 * init and for CPU1, a secure PPA API provided. CPU0 must be ON
 	 * while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
 	 * OMAP443X GP devices- SMP bit isn't accessible.
 	 * OMAP446X GP devices - SMP bit access is enabled on both CPUs.
 	 */
 	if (cpu_is_omap443x() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
 		omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
 							4, 0, 0, 0, 0, 0);

 	/*
 	 * Configure the CNTFRQ register for the secondary cpu's which
 	 * indicates the frequency of the cpu local timers.
 	 */
 	if (soc_is_omap54xx() || soc_is_dra7xx())
 		set_cntfreq();

 	/*
 	 * Synchronise with the boot thread.
 	 */
 	spin_lock(&boot_lock);
 	spin_unlock(&boot_lock);
 }

 static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
 {
 	static struct clockdomain *cpu1_clkdm;
 	static bool booted;
 	static struct powerdomain *cpu1_pwrdm;
 	void __iomem *base = omap_get_wakeupgen_base();

 	/*
 	 * Set synchronisation state between this boot processor
 	 * and the secondary one
 	 */
 	spin_lock(&boot_lock);

 	/*
 	 * Update the AuxCoreBoot0 with boot state for secondary core.
 	 * omap4_secondary_startup() routine will hold the secondary core till
 	 * the AuxCoreBoot1 register is updated with cpu state
 	 * A barrier is added to ensure that write buffer is drained
 	 */
 	if (omap_secure_apis_support())
 		omap_modify_auxcoreboot0(0x200, 0xfffffdff);
 	else
 		writel_relaxed(0x20, base + OMAP_AUX_CORE_BOOT_0);

 	if (!cpu1_clkdm && !cpu1_pwrdm) {
 		cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
 		cpu1_pwrdm = pwrdm_lookup("cpu1_pwrdm");
 	}

 	/*
 	 * The SGI(Software Generated Interrupts) are not wakeup capable
 	 * from low power states. This is known limitation on OMAP4 and
 	 * needs to be worked around by using software forced clockdomain
 	 * wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
 	 * software force wakeup. The clockdomain is then put back to
 	 * hardware supervised mode.
 	 * More details can be found in OMAP4430 TRM - Version J
 	 * Section :
 	 *	4.3.4.2 Power States of CPU0 and CPU1
 	 */
 	if (booted && cpu1_pwrdm && cpu1_clkdm) {
 		/*
 		 * GIC distributor control register has changed between
 		 * CortexA9 r1pX and r2pX. The Control Register secure
 		 * banked version is now composed of 2 bits:
 		 * bit 0 == Secure Enable
 		 * bit 1 == Non-Secure Enable
 		 * The Non-Secure banked register has not changed
 		 * Because the ROM Code is based on the r1pX GIC, the CPU1
 		 * GIC restoration will cause a problem to CPU0 Non-Secure SW.
 		 * The workaround must be:
 		 * 1) Before doing the CPU1 wakeup, CPU0 must disable
 		 * the GIC distributor
 		 * 2) CPU1 must re-enable the GIC distributor on
 		 * it's wakeup path.
 		 */
 		if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
 			local_irq_disable();
 			gic_dist_disable();
 		}

 		/*
 		 * Ensure that CPU power state is set to ON to avoid CPU
 		 * powerdomain transition on wfi
 		 */
 		clkdm_wakeup_nolock(cpu1_clkdm);
 		pwrdm_set_next_pwrst(cpu1_pwrdm, PWRDM_POWER_ON);
 		clkdm_allow_idle_nolock(cpu1_clkdm);

 		if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
 			while (gic_dist_disabled()) {
 				udelay(1);
 				cpu_relax();
 			}
 			gic_timer_retrigger();
 			local_irq_enable();
 		}
 	} else {
 		dsb_sev();
 		booted = true;
 	}

 	arch_send_wakeup_ipi_mask(cpumask_of(cpu));

 	/*
 	 * Now the secondary core is starting up let it run its
 	 * calibrations, then wait for it to finish
 	 */
 	spin_unlock(&boot_lock);

 	return 0;
 }

 /*
  * Initialise the CPU possible map early - this describes the CPUs
  * which may be present or become present in the system.
  */
 static void __init omap4_smp_init_cpus(void)
 {
 	unsigned int i = 0, ncores = 1, cpu_id;

 	/* Use ARM cpuid check here, as SoC detection will not work so early */
 	cpu_id = read_cpuid_id() & CPU_MASK;
 	if (cpu_id == CPU_CORTEX_A9) {
 		/*
 		 * Currently we can't call ioremap here because
 		 * SoC detection won't work until after init_early.
 		 */
 		scu_base =  OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
 		BUG_ON(!scu_base);
 		ncores = scu_get_core_count(scu_base);
 	} else if (cpu_id == CPU_CORTEX_A15) {
 		ncores = OMAP5_CORE_COUNT;
 	}

 	/* sanity check */
 	if (ncores > nr_cpu_ids) {
 		pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
 			ncores, nr_cpu_ids);
 		ncores = nr_cpu_ids;
 	}

 	for (i = 0; i < ncores; i++)
 		set_cpu_possible(i, true);
 }

 static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
 {
 	void *startup_addr = omap4_secondary_startup;
 	void __iomem *base = omap_get_wakeupgen_base();

 	/*
 	 * Initialise the SCU and wake up the secondary core using
 	 * wakeup_secondary().
 	 */
 	if (scu_base)
 		scu_enable(scu_base);

 	if (cpu_is_omap446x())
 		startup_addr = omap4460_secondary_startup;

 	/*
 	 * Write the address of secondary startup routine into the
 	 * AuxCoreBoot1 where ROM code will jump and start executing
 	 * on secondary core once out of WFE
 	 * A barrier is added to ensure that write buffer is drained
 	 */
 	if (omap_secure_apis_support())
 		omap_auxcoreboot_addr(virt_to_phys(startup_addr));
 	else
 		/*
 		 * If the boot CPU is in HYP mode then start secondary
 		 * CPU in HYP mode as well.
 		 */
 		if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE)
 			writel_relaxed(virt_to_phys(omap5_secondary_hyp_startup),
 				       base + OMAP_AUX_CORE_BOOT_1);
 		else
 			writel_relaxed(virt_to_phys(omap5_secondary_startup),
 				       base + OMAP_AUX_CORE_BOOT_1);

 }

 struct smp_operations omap4_smp_ops __initdata = {
 	.smp_init_cpus		= omap4_smp_init_cpus,
 	.smp_prepare_cpus	= omap4_smp_prepare_cpus,
 	.smp_secondary_init	= omap4_secondary_init,
 	.smp_boot_secondary	= omap4_boot_secondary,
 #ifdef CONFIG_HOTPLUG_CPU
 	.cpu_die		= omap4_cpu_die,
 #endif
 };
	/*
	* OMAP4 SMP source file. It contains platform specific functions
	* needed for the linux smp kernel.
	*
	* Copyright (C) 2009 Texas Instruments, Inc.
	*
	* Author:
	* Santosh Shilimkar <santosh.shilimkar@ti.com>
	*
	* Platform file needed for the OMAP4 SMP. This file is based on arm
	* realview smp platform.
	* * Copyright (c) 2002 ARM Limited.
	*
	* 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/init.h>
	#include <linux/device.h>
	#include <linux/smp.h>
	#include <linux/io.h>
	#include <linux/irqchip/arm-gic.h>

	#include <asm/smp_scu.h>
	#include <asm/virt.h>

	#include "omap-secure.h"
	#include "omap-wakeupgen.h"
	#include <asm/cputype.h>

	#include "soc.h"
	#include "iomap.h"
	#include "common.h"
	#include "clockdomain.h"
	#include "pm.h"

	#define CPU_MASK 0xff0ffff0
	#define CPU_CORTEX_A9 0x410FC090
	#define CPU_CORTEX_A15 0x410FC0F0

	#define OMAP5_CORE_COUNT 0x2

	/* SCU base address */
	static void __iomem *scu_base;

	static DEFINE_SPINLOCK(boot_lock);

	void __iomem *omap4_get_scu_base(void)
	{
	return scu_base;
	}

	static void omap4_secondary_init(unsigned int cpu)
	{
	/*
	* Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
	* OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
	* init and for CPU1, a secure PPA API provided. CPU0 must be ON
	* while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
	* OMAP443X GP devices- SMP bit isn't accessible.
	* OMAP446X GP devices - SMP bit access is enabled on both CPUs.
	*/
	if (cpu_is_omap443x() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
	omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
	4, 0, 0, 0, 0, 0);

	/*
	* Configure the CNTFRQ register for the secondary cpu's which
	* indicates the frequency of the cpu local timers.
	*/
	if (soc_is_omap54xx() \|\| soc_is_dra7xx())
	set_cntfreq();

	/*
	* Synchronise with the boot thread.
	*/
	spin_lock(&boot_lock);
	spin_unlock(&boot_lock);
	}

	static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
	{
	static struct clockdomain *cpu1_clkdm;
	static bool booted;
	static struct powerdomain *cpu1_pwrdm;
	void __iomem *base = omap_get_wakeupgen_base();

	/*
	* Set synchronisation state between this boot processor
	* and the secondary one
	*/
	spin_lock(&boot_lock);

	/*
	* Update the AuxCoreBoot0 with boot state for secondary core.
	* omap4_secondary_startup() routine will hold the secondary core till
	* the AuxCoreBoot1 register is updated with cpu state
	* A barrier is added to ensure that write buffer is drained
	*/
	if (omap_secure_apis_support())
	omap_modify_auxcoreboot0(0x200, 0xfffffdff);
	else
	writel_relaxed(0x20, base + OMAP_AUX_CORE_BOOT_0);

	if (!cpu1_clkdm && !cpu1_pwrdm) {
	cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
	cpu1_pwrdm = pwrdm_lookup("cpu1_pwrdm");
	}

	/*
	* The SGI(Software Generated Interrupts) are not wakeup capable
	* from low power states. This is known limitation on OMAP4 and
	* needs to be worked around by using software forced clockdomain
	* wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
	* software force wakeup. The clockdomain is then put back to
	* hardware supervised mode.
	* More details can be found in OMAP4430 TRM - Version J
	* Section :
	* 4.3.4.2 Power States of CPU0 and CPU1
	*/
	if (booted && cpu1_pwrdm && cpu1_clkdm) {
	/*
	* GIC distributor control register has changed between
	* CortexA9 r1pX and r2pX. The Control Register secure
	* banked version is now composed of 2 bits:
	* bit 0 == Secure Enable
	* bit 1 == Non-Secure Enable
	* The Non-Secure banked register has not changed
	* Because the ROM Code is based on the r1pX GIC, the CPU1
	* GIC restoration will cause a problem to CPU0 Non-Secure SW.
	* The workaround must be:
	* 1) Before doing the CPU1 wakeup, CPU0 must disable
	* the GIC distributor
	* 2) CPU1 must re-enable the GIC distributor on
	* it's wakeup path.
	*/
	if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
	local_irq_disable();
	gic_dist_disable();
	}

	/*
	* Ensure that CPU power state is set to ON to avoid CPU
	* powerdomain transition on wfi
	*/
	clkdm_wakeup_nolock(cpu1_clkdm);
	pwrdm_set_next_pwrst(cpu1_pwrdm, PWRDM_POWER_ON);
	clkdm_allow_idle_nolock(cpu1_clkdm);

	if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
	while (gic_dist_disabled()) {
	udelay(1);
	cpu_relax();
	}
	gic_timer_retrigger();
	local_irq_enable();
	}
	} else {
	dsb_sev();
	booted = true;
	}

	arch_send_wakeup_ipi_mask(cpumask_of(cpu));

	/*
	* Now the secondary core is starting up let it run its
	* calibrations, then wait for it to finish
	*/
	spin_unlock(&boot_lock);

	return 0;
	}

	/*
	* Initialise the CPU possible map early - this describes the CPUs
	* which may be present or become present in the system.
	*/
	static void __init omap4_smp_init_cpus(void)
	{
	unsigned int i = 0, ncores = 1, cpu_id;

	/* Use ARM cpuid check here, as SoC detection will not work so early */
	cpu_id = read_cpuid_id() & CPU_MASK;
	if (cpu_id == CPU_CORTEX_A9) {
	/*
	* Currently we can't call ioremap here because
	* SoC detection won't work until after init_early.
	*/
	scu_base = OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
	BUG_ON(!scu_base);
	ncores = scu_get_core_count(scu_base);
	} else if (cpu_id == CPU_CORTEX_A15) {
	ncores = OMAP5_CORE_COUNT;
	}

	/* sanity check */
	if (ncores > nr_cpu_ids) {
	pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
	ncores, nr_cpu_ids);
	ncores = nr_cpu_ids;
	}

	for (i = 0; i < ncores; i++)
	set_cpu_possible(i, true);
	}

	static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
	{
	void *startup_addr = omap4_secondary_startup;
	void __iomem *base = omap_get_wakeupgen_base();

	/*
	* Initialise the SCU and wake up the secondary core using
	* wakeup_secondary().
	*/
	if (scu_base)
	scu_enable(scu_base);

	if (cpu_is_omap446x())
	startup_addr = omap4460_secondary_startup;

	/*
	* Write the address of secondary startup routine into the
	* AuxCoreBoot1 where ROM code will jump and start executing
	* on secondary core once out of WFE
	* A barrier is added to ensure that write buffer is drained
	*/
	if (omap_secure_apis_support())
	omap_auxcoreboot_addr(virt_to_phys(startup_addr));
	else
	/*
	* If the boot CPU is in HYP mode then start secondary
	* CPU in HYP mode as well.
	*/
	if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE)
	writel_relaxed(virt_to_phys(omap5_secondary_hyp_startup),
	base + OMAP_AUX_CORE_BOOT_1);
	else
	writel_relaxed(virt_to_phys(omap5_secondary_startup),
	base + OMAP_AUX_CORE_BOOT_1);

	}

	struct smp_operations omap4_smp_ops __initdata = {
	.smp_init_cpus = omap4_smp_init_cpus,
	.smp_prepare_cpus = omap4_smp_prepare_cpus,
	.smp_secondary_init = omap4_secondary_init,
	.smp_boot_secondary = omap4_boot_secondary,
	#ifdef CONFIG_HOTPLUG_CPU
	.cpu_die = omap4_cpu_die,
	#endif
	};