arch/mips/kernel/smp-bmips.c - kernel/msm-4.9 - Gitiles

 /*
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
  * Copyright (C) 2011 by Kevin Cernekee (cernekee@gmail.com)
  *
  * SMP support for BMIPS
  */

 #include <linux/version.h>
 #include <linux/init.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/delay.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
 #include <linux/init.h>
 #include <linux/cpu.h>
 #include <linux/cpumask.h>
 #include <linux/reboot.h>
 #include <linux/io.h>
 #include <linux/compiler.h>
 #include <linux/linkage.h>
 #include <linux/bug.h>
 #include <linux/kernel.h>

 #include <asm/time.h>
 #include <asm/pgtable.h>
 #include <asm/processor.h>
 #include <asm/system.h>
 #include <asm/bootinfo.h>
 #include <asm/pmon.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 #include <asm/mipsregs.h>
 #include <asm/bmips.h>
 #include <asm/traps.h>
 #include <asm/barrier.h>

 static int __maybe_unused max_cpus = 1;

 /* these may be configured by the platform code */
 int bmips_smp_enabled = 1;
 int bmips_cpu_offset;
 cpumask_t bmips_booted_mask;

 #ifdef CONFIG_SMP

 /* initial $sp, $gp - used by arch/mips/kernel/bmips_vec.S */
 unsigned long bmips_smp_boot_sp;
 unsigned long bmips_smp_boot_gp;

 static void bmips_send_ipi_single(int cpu, unsigned int action);
 static irqreturn_t bmips_ipi_interrupt(int irq, void *dev_id);

 /* SW interrupts 0,1 are used for interprocessor signaling */
 #define IPI0_IRQ			(MIPS_CPU_IRQ_BASE + 0)
 #define IPI1_IRQ			(MIPS_CPU_IRQ_BASE + 1)

 #define CPUNUM(cpu, shift)		(((cpu) + bmips_cpu_offset) << (shift))
 #define ACTION_CLR_IPI(cpu, ipi)	(0x2000 | CPUNUM(cpu, 9) | ((ipi) << 8))
 #define ACTION_SET_IPI(cpu, ipi)	(0x3000 | CPUNUM(cpu, 9) | ((ipi) << 8))
 #define ACTION_BOOT_THREAD(cpu)		(0x08 | CPUNUM(cpu, 0))

 static void __init bmips_smp_setup(void)
 {
 	int i;

 #if defined(CONFIG_CPU_BMIPS4350) || defined(CONFIG_CPU_BMIPS4380)
 	/* arbitration priority */
 	clear_c0_brcm_cmt_ctrl(0x30);

 	/* NBK and weak order flags */
 	set_c0_brcm_config_0(0x30000);

 	/*
 	 * MIPS interrupts 0,1 (SW INT 0,1) cross over to the other thread
 	 * MIPS interrupt 2 (HW INT 0) is the CPU0 L1 controller output
 	 * MIPS interrupt 3 (HW INT 1) is the CPU1 L1 controller output
 	 */
 	change_c0_brcm_cmt_intr(0xf8018000,
 		(0x02 << 27) | (0x03 << 15));

 	/* single core, 2 threads (2 pipelines) */
 	max_cpus = 2;
 #elif defined(CONFIG_CPU_BMIPS5000)
 	/* enable raceless SW interrupts */
 	set_c0_brcm_config(0x03 << 22);

 	/* route HW interrupt 0 to CPU0, HW interrupt 1 to CPU1 */
 	change_c0_brcm_mode(0x1f << 27, 0x02 << 27);

 	/* N cores, 2 threads per core */
 	max_cpus = (((read_c0_brcm_config() >> 6) & 0x03) + 1) << 1;

 	/* clear any pending SW interrupts */
 	for (i = 0; i < max_cpus; i++) {
 		write_c0_brcm_action(ACTION_CLR_IPI(i, 0));
 		write_c0_brcm_action(ACTION_CLR_IPI(i, 1));
 	}
 #endif

 	if (!bmips_smp_enabled)
 		max_cpus = 1;

 	/* this can be overridden by the BSP */
 	if (!board_ebase_setup)
 		board_ebase_setup = &bmips_ebase_setup;

 	for (i = 0; i < max_cpus; i++) {
 		__cpu_number_map[i] = 1;
 		__cpu_logical_map[i] = 1;
 		set_cpu_possible(i, 1);
 		set_cpu_present(i, 1);
 	}
 }

 /*
  * IPI IRQ setup - runs on CPU0
  */
 static void bmips_prepare_cpus(unsigned int max_cpus)
 {
 	if (request_irq(IPI0_IRQ, bmips_ipi_interrupt, IRQF_PERCPU,
 			"smp_ipi0", NULL))
 		panic("Can't request IPI0 interrupt\n");
 	if (request_irq(IPI1_IRQ, bmips_ipi_interrupt, IRQF_PERCPU,
 			"smp_ipi1", NULL))
 		panic("Can't request IPI1 interrupt\n");
 }

 /*
  * Tell the hardware to boot CPUx - runs on CPU0
  */
 static void bmips_boot_secondary(int cpu, struct task_struct *idle)
 {
 	bmips_smp_boot_sp = __KSTK_TOS(idle);
 	bmips_smp_boot_gp = (unsigned long)task_thread_info(idle);
 	mb();

 	/*
 	 * Initial boot sequence for secondary CPU:
 	 *   bmips_reset_nmi_vec @ a000_0000 ->
 	 *   bmips_smp_entry ->
 	 *   plat_wired_tlb_setup (cached function call; optional) ->
 	 *   start_secondary (cached jump)
 	 *
 	 * Warm restart sequence:
 	 *   play_dead WAIT loop ->
 	 *   bmips_smp_int_vec @ BMIPS_WARM_RESTART_VEC ->
 	 *   eret to play_dead ->
 	 *   bmips_secondary_reentry ->
 	 *   start_secondary
 	 */

 	pr_info("SMP: Booting CPU%d...\n", cpu);

 	if (cpumask_test_cpu(cpu, &bmips_booted_mask))
 		bmips_send_ipi_single(cpu, 0);
 	else {
 #if defined(CONFIG_CPU_BMIPS4350) || defined(CONFIG_CPU_BMIPS4380)
 		set_c0_brcm_cmt_ctrl(0x01);
 #elif defined(CONFIG_CPU_BMIPS5000)
 		if (cpu & 0x01)
 			write_c0_brcm_action(ACTION_BOOT_THREAD(cpu));
 		else {
 			/*
 			 * core N thread 0 was already booted; just
 			 * pulse the NMI line
 			 */
 			bmips_write_zscm_reg(0x210, 0xc0000000);
 			udelay(10);
 			bmips_write_zscm_reg(0x210, 0x00);
 		}
 #endif
 		cpumask_set_cpu(cpu, &bmips_booted_mask);
 	}
 }

 /*
  * Early setup - runs on secondary CPU after cache probe
  */
 static void bmips_init_secondary(void)
 {
 	/* move NMI vector to kseg0, in case XKS01 is enabled */

 #if defined(CONFIG_CPU_BMIPS4350) || defined(CONFIG_CPU_BMIPS4380)
 	void __iomem *cbr = BMIPS_GET_CBR();
 	unsigned long old_vec;

 	old_vec = __raw_readl(cbr + BMIPS_RELO_VECTOR_CONTROL_1);
 	__raw_writel(old_vec & ~0x20000000, cbr + BMIPS_RELO_VECTOR_CONTROL_1);

 	clear_c0_cause(smp_processor_id() ? C_SW1 : C_SW0);
 #elif defined(CONFIG_CPU_BMIPS5000)
 	write_c0_brcm_bootvec(read_c0_brcm_bootvec() &
 		(smp_processor_id() & 0x01 ? ~0x20000000 : ~0x2000));

 	write_c0_brcm_action(ACTION_CLR_IPI(smp_processor_id(), 0));
 #endif

 	/* make sure there won't be a timer interrupt for a little while */
 	write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);

 	irq_enable_hazard();
 	set_c0_status(IE_SW0 | IE_SW1 | IE_IRQ1 | IE_IRQ5 | ST0_IE);
 	irq_enable_hazard();
 }

 /*
  * Late setup - runs on secondary CPU before entering the idle loop
  */
 static void bmips_smp_finish(void)
 {
 	pr_info("SMP: CPU%d is running\n", smp_processor_id());
 }

 /*
  * Runs on CPU0 after all CPUs have been booted
  */
 static void bmips_cpus_done(void)
 {
 }

 #if defined(CONFIG_CPU_BMIPS5000)

 /*
  * BMIPS5000 raceless IPIs
  *
  * Each CPU has two inbound SW IRQs which are independent of all other CPUs.
  * IPI0 is used for SMP_RESCHEDULE_YOURSELF
  * IPI1 is used for SMP_CALL_FUNCTION
  */

 static void bmips_send_ipi_single(int cpu, unsigned int action)
 {
 	write_c0_brcm_action(ACTION_SET_IPI(cpu, action == SMP_CALL_FUNCTION));
 }

 static irqreturn_t bmips_ipi_interrupt(int irq, void *dev_id)
 {
 	int action = irq - IPI0_IRQ;

 	write_c0_brcm_action(ACTION_CLR_IPI(smp_processor_id(), action));

 	if (action == 0)
 		scheduler_ipi();
 	else
 		smp_call_function_interrupt();

 	return IRQ_HANDLED;
 }

 #else

 /*
  * BMIPS43xx racey IPIs
  *
  * We use one inbound SW IRQ for each CPU.
  *
  * A spinlock must be held in order to keep CPUx from accidentally clearing
  * an incoming IPI when it writes CP0 CAUSE to raise an IPI on CPUy.  The
  * same spinlock is used to protect the action masks.
  */

 static DEFINE_SPINLOCK(ipi_lock);
 static DEFINE_PER_CPU(int, ipi_action_mask);

 static void bmips_send_ipi_single(int cpu, unsigned int action)
 {
 	unsigned long flags;

 	spin_lock_irqsave(&ipi_lock, flags);
 	set_c0_cause(cpu ? C_SW1 : C_SW0);
 	per_cpu(ipi_action_mask, cpu) |= action;
 	irq_enable_hazard();
 	spin_unlock_irqrestore(&ipi_lock, flags);
 }

 static irqreturn_t bmips_ipi_interrupt(int irq, void *dev_id)
 {
 	unsigned long flags;
 	int action, cpu = irq - IPI0_IRQ;

 	spin_lock_irqsave(&ipi_lock, flags);
 	action = __get_cpu_var(ipi_action_mask);
 	per_cpu(ipi_action_mask, cpu) = 0;
 	clear_c0_cause(cpu ? C_SW1 : C_SW0);
 	spin_unlock_irqrestore(&ipi_lock, flags);

 	if (action & SMP_RESCHEDULE_YOURSELF)
 		scheduler_ipi();
 	if (action & SMP_CALL_FUNCTION)
 		smp_call_function_interrupt();

 	return IRQ_HANDLED;
 }

 #endif /* BMIPS type */

 static void bmips_send_ipi_mask(const struct cpumask *mask,
 	unsigned int action)
 {
 	unsigned int i;

 	for_each_cpu(i, mask)
 		bmips_send_ipi_single(i, action);
 }

 #ifdef CONFIG_HOTPLUG_CPU

 static int bmips_cpu_disable(void)
 {
 	unsigned int cpu = smp_processor_id();

 	if (cpu == 0)
 		return -EBUSY;

 	pr_info("SMP: CPU%d is offline\n", cpu);

 	cpu_clear(cpu, cpu_online_map);
 	cpu_clear(cpu, cpu_callin_map);

 	local_flush_tlb_all();
 	local_flush_icache_range(0, ~0);

 	return 0;
 }

 static void bmips_cpu_die(unsigned int cpu)
 {
 }

 void __ref play_dead(void)
 {
 	idle_task_exit();

 	/* flush data cache */
 	_dma_cache_wback_inv(0, ~0);

 	/*
 	 * Wakeup is on SW0 or SW1; disable everything else
 	 * Use BEV !IV (BMIPS_WARM_RESTART_VEC) to avoid the regular Linux
 	 * IRQ handlers; this clears ST0_IE and returns immediately.
 	 */
 	clear_c0_cause(CAUSEF_IV | C_SW0 | C_SW1);
 	change_c0_status(IE_IRQ5 | IE_IRQ1 | IE_SW0 | IE_SW1 | ST0_IE | ST0_BEV,
 		IE_SW0 | IE_SW1 | ST0_IE | ST0_BEV);
 	irq_disable_hazard();

 	/*
 	 * wait for SW interrupt from bmips_boot_secondary(), then jump
 	 * back to start_secondary()
 	 */
 	__asm__ __volatile__(
 	"	wait\n"
 	"	j	bmips_secondary_reentry\n"
 	: : : "memory");
 }

 #endif /* CONFIG_HOTPLUG_CPU */

 struct plat_smp_ops bmips_smp_ops = {
 	.smp_setup		= bmips_smp_setup,
 	.prepare_cpus		= bmips_prepare_cpus,
 	.boot_secondary		= bmips_boot_secondary,
 	.smp_finish		= bmips_smp_finish,
 	.init_secondary		= bmips_init_secondary,
 	.cpus_done		= bmips_cpus_done,
 	.send_ipi_single	= bmips_send_ipi_single,
 	.send_ipi_mask		= bmips_send_ipi_mask,
 #ifdef CONFIG_HOTPLUG_CPU
 	.cpu_disable		= bmips_cpu_disable,
 	.cpu_die		= bmips_cpu_die,
 #endif
 };

 #endif /* CONFIG_SMP */

 /***********************************************************************
  * BMIPS vector relocation
  * This is primarily used for SMP boot, but it is applicable to some
  * UP BMIPS systems as well.
  ***********************************************************************/

 static void __cpuinit bmips_wr_vec(unsigned long dst, char *start, char *end)
 {
 	memcpy((void *)dst, start, end - start);
 	dma_cache_wback((unsigned long)start, end - start);
 	local_flush_icache_range(dst, dst + (end - start));
 	instruction_hazard();
 }

 static inline void __cpuinit bmips_nmi_handler_setup(void)
 {
 	bmips_wr_vec(BMIPS_NMI_RESET_VEC, &bmips_reset_nmi_vec,
 		&bmips_reset_nmi_vec_end);
 	bmips_wr_vec(BMIPS_WARM_RESTART_VEC, &bmips_smp_int_vec,
 		&bmips_smp_int_vec_end);
 }

 void __cpuinit bmips_ebase_setup(void)
 {
 	unsigned long new_ebase = ebase;
 	void __iomem __maybe_unused *cbr;

 	BUG_ON(ebase != CKSEG0);

 #if defined(CONFIG_CPU_BMIPS4350)
 	/*
 	 * BMIPS4350 cannot relocate the normal vectors, but it
 	 * can relocate the BEV=1 vectors.  So CPU1 starts up at
 	 * the relocated BEV=1, IV=0 general exception vector @
 	 * 0xa000_0380.
 	 *
 	 * set_uncached_handler() is used here because:
 	 *  - CPU1 will run this from uncached space
 	 *  - None of the cacheflush functions are set up yet
 	 */
 	set_uncached_handler(BMIPS_WARM_RESTART_VEC - CKSEG0,
 		&bmips_smp_int_vec, 0x80);
 	__sync();
 	return;
 #elif defined(CONFIG_CPU_BMIPS4380)
 	/*
 	 * 0x8000_0000: reset/NMI (initially in kseg1)
 	 * 0x8000_0400: normal vectors
 	 */
 	new_ebase = 0x80000400;
 	cbr = BMIPS_GET_CBR();
 	__raw_writel(0x80080800, cbr + BMIPS_RELO_VECTOR_CONTROL_0);
 	__raw_writel(0xa0080800, cbr + BMIPS_RELO_VECTOR_CONTROL_1);
 #elif defined(CONFIG_CPU_BMIPS5000)
 	/*
 	 * 0x8000_0000: reset/NMI (initially in kseg1)
 	 * 0x8000_1000: normal vectors
 	 */
 	new_ebase = 0x80001000;
 	write_c0_brcm_bootvec(0xa0088008);
 	write_c0_ebase(new_ebase);
 	if (max_cpus > 2)
 		bmips_write_zscm_reg(0xa0, 0xa008a008);
 #else
 	return;
 #endif
 	board_nmi_handler_setup = &bmips_nmi_handler_setup;
 	ebase = new_ebase;
 }

 asmlinkage void __weak plat_wired_tlb_setup(void)
 {
 	/*
 	 * Called when starting/restarting a secondary CPU.
 	 * Kernel stacks and other important data might only be accessible
 	 * once the wired entries are present.
 	 */
 }
	/*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*
	* Copyright (C) 2011 by Kevin Cernekee (cernekee@gmail.com)
	*
	* SMP support for BMIPS
	*/

	#include <linux/version.h>
	#include <linux/init.h>
	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/delay.h>
	#include <linux/smp.h>
	#include <linux/interrupt.h>
	#include <linux/spinlock.h>
	#include <linux/init.h>
	#include <linux/cpu.h>
	#include <linux/cpumask.h>
	#include <linux/reboot.h>
	#include <linux/io.h>
	#include <linux/compiler.h>
	#include <linux/linkage.h>
	#include <linux/bug.h>
	#include <linux/kernel.h>

	#include <asm/time.h>
	#include <asm/pgtable.h>
	#include <asm/processor.h>
	#include <asm/system.h>
	#include <asm/bootinfo.h>
	#include <asm/pmon.h>
	#include <asm/cacheflush.h>
	#include <asm/tlbflush.h>
	#include <asm/mipsregs.h>
	#include <asm/bmips.h>
	#include <asm/traps.h>
	#include <asm/barrier.h>

	static int __maybe_unused max_cpus = 1;

	/* these may be configured by the platform code */
	int bmips_smp_enabled = 1;
	int bmips_cpu_offset;
	cpumask_t bmips_booted_mask;

	#ifdef CONFIG_SMP

	/* initial $sp, $gp - used by arch/mips/kernel/bmips_vec.S */
	unsigned long bmips_smp_boot_sp;
	unsigned long bmips_smp_boot_gp;

	static void bmips_send_ipi_single(int cpu, unsigned int action);
	static irqreturn_t bmips_ipi_interrupt(int irq, void *dev_id);

	/* SW interrupts 0,1 are used for interprocessor signaling */
	#define IPI0_IRQ (MIPS_CPU_IRQ_BASE + 0)
	#define IPI1_IRQ (MIPS_CPU_IRQ_BASE + 1)

	#define CPUNUM(cpu, shift) (((cpu) + bmips_cpu_offset) << (shift))
	#define ACTION_CLR_IPI(cpu, ipi) (0x2000 \| CPUNUM(cpu, 9) \| ((ipi) << 8))
	#define ACTION_SET_IPI(cpu, ipi) (0x3000 \| CPUNUM(cpu, 9) \| ((ipi) << 8))
	#define ACTION_BOOT_THREAD(cpu) (0x08 \| CPUNUM(cpu, 0))

	static void __init bmips_smp_setup(void)
	{
	int i;

	#if defined(CONFIG_CPU_BMIPS4350) \|\| defined(CONFIG_CPU_BMIPS4380)
	/* arbitration priority */
	clear_c0_brcm_cmt_ctrl(0x30);

	/* NBK and weak order flags */
	set_c0_brcm_config_0(0x30000);

	/*
	* MIPS interrupts 0,1 (SW INT 0,1) cross over to the other thread
	* MIPS interrupt 2 (HW INT 0) is the CPU0 L1 controller output
	* MIPS interrupt 3 (HW INT 1) is the CPU1 L1 controller output
	*/
	change_c0_brcm_cmt_intr(0xf8018000,
	(0x02 << 27) \| (0x03 << 15));

	/* single core, 2 threads (2 pipelines) */
	max_cpus = 2;
	#elif defined(CONFIG_CPU_BMIPS5000)
	/* enable raceless SW interrupts */
	set_c0_brcm_config(0x03 << 22);

	/* route HW interrupt 0 to CPU0, HW interrupt 1 to CPU1 */
	change_c0_brcm_mode(0x1f << 27, 0x02 << 27);

	/* N cores, 2 threads per core */
	max_cpus = (((read_c0_brcm_config() >> 6) & 0x03) + 1) << 1;

	/* clear any pending SW interrupts */
	for (i = 0; i < max_cpus; i++) {
	write_c0_brcm_action(ACTION_CLR_IPI(i, 0));
	write_c0_brcm_action(ACTION_CLR_IPI(i, 1));
	}
	#endif

	if (!bmips_smp_enabled)
	max_cpus = 1;

	/* this can be overridden by the BSP */
	if (!board_ebase_setup)
	board_ebase_setup = &bmips_ebase_setup;

	for (i = 0; i < max_cpus; i++) {
	__cpu_number_map[i] = 1;
	__cpu_logical_map[i] = 1;
	set_cpu_possible(i, 1);
	set_cpu_present(i, 1);
	}
	}

	/*
	* IPI IRQ setup - runs on CPU0
	*/
	static void bmips_prepare_cpus(unsigned int max_cpus)
	{
	if (request_irq(IPI0_IRQ, bmips_ipi_interrupt, IRQF_PERCPU,
	"smp_ipi0", NULL))
	panic("Can't request IPI0 interrupt\n");
	if (request_irq(IPI1_IRQ, bmips_ipi_interrupt, IRQF_PERCPU,
	"smp_ipi1", NULL))
	panic("Can't request IPI1 interrupt\n");
	}

	/*
	* Tell the hardware to boot CPUx - runs on CPU0
	*/
	static void bmips_boot_secondary(int cpu, struct task_struct *idle)
	{
	bmips_smp_boot_sp = __KSTK_TOS(idle);
	bmips_smp_boot_gp = (unsigned long)task_thread_info(idle);
	mb();

	/*
	* Initial boot sequence for secondary CPU:
	* bmips_reset_nmi_vec @ a000_0000 ->
	* bmips_smp_entry ->
	* plat_wired_tlb_setup (cached function call; optional) ->
	* start_secondary (cached jump)
	*
	* Warm restart sequence:
	* play_dead WAIT loop ->
	* bmips_smp_int_vec @ BMIPS_WARM_RESTART_VEC ->
	* eret to play_dead ->
	* bmips_secondary_reentry ->
	* start_secondary
	*/

	pr_info("SMP: Booting CPU%d...\n", cpu);

	if (cpumask_test_cpu(cpu, &bmips_booted_mask))
	bmips_send_ipi_single(cpu, 0);
	else {
	#if defined(CONFIG_CPU_BMIPS4350) \|\| defined(CONFIG_CPU_BMIPS4380)
	set_c0_brcm_cmt_ctrl(0x01);
	#elif defined(CONFIG_CPU_BMIPS5000)
	if (cpu & 0x01)
	write_c0_brcm_action(ACTION_BOOT_THREAD(cpu));
	else {
	/*
	* core N thread 0 was already booted; just
	* pulse the NMI line
	*/
	bmips_write_zscm_reg(0x210, 0xc0000000);
	udelay(10);
	bmips_write_zscm_reg(0x210, 0x00);
	}
	#endif
	cpumask_set_cpu(cpu, &bmips_booted_mask);
	}
	}

	/*
	* Early setup - runs on secondary CPU after cache probe
	*/
	static void bmips_init_secondary(void)
	{
	/* move NMI vector to kseg0, in case XKS01 is enabled */

	#if defined(CONFIG_CPU_BMIPS4350) \|\| defined(CONFIG_CPU_BMIPS4380)
	void __iomem *cbr = BMIPS_GET_CBR();
	unsigned long old_vec;

	old_vec = __raw_readl(cbr + BMIPS_RELO_VECTOR_CONTROL_1);
	__raw_writel(old_vec & ~0x20000000, cbr + BMIPS_RELO_VECTOR_CONTROL_1);

	clear_c0_cause(smp_processor_id() ? C_SW1 : C_SW0);
	#elif defined(CONFIG_CPU_BMIPS5000)
	write_c0_brcm_bootvec(read_c0_brcm_bootvec() &
	(smp_processor_id() & 0x01 ? ~0x20000000 : ~0x2000));

	write_c0_brcm_action(ACTION_CLR_IPI(smp_processor_id(), 0));
	#endif

	/* make sure there won't be a timer interrupt for a little while */
	write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);

	irq_enable_hazard();
	set_c0_status(IE_SW0 \| IE_SW1 \| IE_IRQ1 \| IE_IRQ5 \| ST0_IE);
	irq_enable_hazard();
	}

	/*
	* Late setup - runs on secondary CPU before entering the idle loop
	*/
	static void bmips_smp_finish(void)
	{
	pr_info("SMP: CPU%d is running\n", smp_processor_id());
	}

	/*
	* Runs on CPU0 after all CPUs have been booted
	*/
	static void bmips_cpus_done(void)
	{
	}

	#if defined(CONFIG_CPU_BMIPS5000)

	/*
	* BMIPS5000 raceless IPIs
	*
	* Each CPU has two inbound SW IRQs which are independent of all other CPUs.
	* IPI0 is used for SMP_RESCHEDULE_YOURSELF
	* IPI1 is used for SMP_CALL_FUNCTION
	*/

	static void bmips_send_ipi_single(int cpu, unsigned int action)
	{
	write_c0_brcm_action(ACTION_SET_IPI(cpu, action == SMP_CALL_FUNCTION));
	}

	static irqreturn_t bmips_ipi_interrupt(int irq, void *dev_id)
	{
	int action = irq - IPI0_IRQ;

	write_c0_brcm_action(ACTION_CLR_IPI(smp_processor_id(), action));

	if (action == 0)
	scheduler_ipi();
	else
	smp_call_function_interrupt();

	return IRQ_HANDLED;
	}

	#else

	/*
	* BMIPS43xx racey IPIs
	*
	* We use one inbound SW IRQ for each CPU.
	*
	* A spinlock must be held in order to keep CPUx from accidentally clearing
	* an incoming IPI when it writes CP0 CAUSE to raise an IPI on CPUy. The
	* same spinlock is used to protect the action masks.
	*/

	static DEFINE_SPINLOCK(ipi_lock);
	static DEFINE_PER_CPU(int, ipi_action_mask);

	static void bmips_send_ipi_single(int cpu, unsigned int action)
	{
	unsigned long flags;

	spin_lock_irqsave(&ipi_lock, flags);
	set_c0_cause(cpu ? C_SW1 : C_SW0);
	per_cpu(ipi_action_mask, cpu) \|= action;
	irq_enable_hazard();
	spin_unlock_irqrestore(&ipi_lock, flags);
	}

	static irqreturn_t bmips_ipi_interrupt(int irq, void *dev_id)
	{
	unsigned long flags;
	int action, cpu = irq - IPI0_IRQ;

	spin_lock_irqsave(&ipi_lock, flags);
	action = __get_cpu_var(ipi_action_mask);
	per_cpu(ipi_action_mask, cpu) = 0;
	clear_c0_cause(cpu ? C_SW1 : C_SW0);
	spin_unlock_irqrestore(&ipi_lock, flags);

	if (action & SMP_RESCHEDULE_YOURSELF)
	scheduler_ipi();
	if (action & SMP_CALL_FUNCTION)
	smp_call_function_interrupt();

	return IRQ_HANDLED;
	}

	#endif /* BMIPS type */

	static void bmips_send_ipi_mask(const struct cpumask *mask,
	unsigned int action)
	{
	unsigned int i;

	for_each_cpu(i, mask)
	bmips_send_ipi_single(i, action);
	}

	#ifdef CONFIG_HOTPLUG_CPU

	static int bmips_cpu_disable(void)
	{
	unsigned int cpu = smp_processor_id();

	if (cpu == 0)
	return -EBUSY;

	pr_info("SMP: CPU%d is offline\n", cpu);

	cpu_clear(cpu, cpu_online_map);
	cpu_clear(cpu, cpu_callin_map);

	local_flush_tlb_all();
	local_flush_icache_range(0, ~0);

	return 0;
	}

	static void bmips_cpu_die(unsigned int cpu)
	{
	}

	void __ref play_dead(void)
	{
	idle_task_exit();

	/* flush data cache */
	_dma_cache_wback_inv(0, ~0);

	/*
	* Wakeup is on SW0 or SW1; disable everything else
	* Use BEV !IV (BMIPS_WARM_RESTART_VEC) to avoid the regular Linux
	* IRQ handlers; this clears ST0_IE and returns immediately.
	*/
	clear_c0_cause(CAUSEF_IV \| C_SW0 \| C_SW1);
	change_c0_status(IE_IRQ5 \| IE_IRQ1 \| IE_SW0 \| IE_SW1 \| ST0_IE \| ST0_BEV,
	IE_SW0 \| IE_SW1 \| ST0_IE \| ST0_BEV);
	irq_disable_hazard();

	/*
	* wait for SW interrupt from bmips_boot_secondary(), then jump
	* back to start_secondary()
	*/
	__asm__ __volatile__(
	" wait\n"
	" j bmips_secondary_reentry\n"
	: : : "memory");
	}

	#endif /* CONFIG_HOTPLUG_CPU */

	struct plat_smp_ops bmips_smp_ops = {
	.smp_setup = bmips_smp_setup,
	.prepare_cpus = bmips_prepare_cpus,
	.boot_secondary = bmips_boot_secondary,
	.smp_finish = bmips_smp_finish,
	.init_secondary = bmips_init_secondary,
	.cpus_done = bmips_cpus_done,
	.send_ipi_single = bmips_send_ipi_single,
	.send_ipi_mask = bmips_send_ipi_mask,
	#ifdef CONFIG_HOTPLUG_CPU
	.cpu_disable = bmips_cpu_disable,
	.cpu_die = bmips_cpu_die,
	#endif
	};

	#endif /* CONFIG_SMP */

	/***********************************************************************
	* BMIPS vector relocation
	* This is primarily used for SMP boot, but it is applicable to some
	* UP BMIPS systems as well.
	***********************************************************************/

	static void __cpuinit bmips_wr_vec(unsigned long dst, char start, char end)
	{
	memcpy((void *)dst, start, end - start);
	dma_cache_wback((unsigned long)start, end - start);
	local_flush_icache_range(dst, dst + (end - start));
	instruction_hazard();
	}

	static inline void __cpuinit bmips_nmi_handler_setup(void)
	{
	bmips_wr_vec(BMIPS_NMI_RESET_VEC, &bmips_reset_nmi_vec,
	&bmips_reset_nmi_vec_end);
	bmips_wr_vec(BMIPS_WARM_RESTART_VEC, &bmips_smp_int_vec,
	&bmips_smp_int_vec_end);
	}

	void __cpuinit bmips_ebase_setup(void)
	{
	unsigned long new_ebase = ebase;
	void __iomem __maybe_unused *cbr;

	BUG_ON(ebase != CKSEG0);

	#if defined(CONFIG_CPU_BMIPS4350)
	/*
	* BMIPS4350 cannot relocate the normal vectors, but it
	* can relocate the BEV=1 vectors. So CPU1 starts up at
	* the relocated BEV=1, IV=0 general exception vector @
	* 0xa000_0380.
	*
	* set_uncached_handler() is used here because:
	* - CPU1 will run this from uncached space
	* - None of the cacheflush functions are set up yet
	*/
	set_uncached_handler(BMIPS_WARM_RESTART_VEC - CKSEG0,
	&bmips_smp_int_vec, 0x80);
	__sync();
	return;
	#elif defined(CONFIG_CPU_BMIPS4380)
	/*
	* 0x8000_0000: reset/NMI (initially in kseg1)
	* 0x8000_0400: normal vectors
	*/
	new_ebase = 0x80000400;
	cbr = BMIPS_GET_CBR();
	__raw_writel(0x80080800, cbr + BMIPS_RELO_VECTOR_CONTROL_0);
	__raw_writel(0xa0080800, cbr + BMIPS_RELO_VECTOR_CONTROL_1);
	#elif defined(CONFIG_CPU_BMIPS5000)
	/*
	* 0x8000_0000: reset/NMI (initially in kseg1)
	* 0x8000_1000: normal vectors
	*/
	new_ebase = 0x80001000;
	write_c0_brcm_bootvec(0xa0088008);
	write_c0_ebase(new_ebase);
	if (max_cpus > 2)
	bmips_write_zscm_reg(0xa0, 0xa008a008);
	#else
	return;
	#endif
	board_nmi_handler_setup = &bmips_nmi_handler_setup;
	ebase = new_ebase;
	}

	asmlinkage void __weak plat_wired_tlb_setup(void)
	{
	/*
	* Called when starting/restarting a secondary CPU.
	* Kernel stacks and other important data might only be accessible
	* once the wired entries are present.
	*/
	}