diff options
Diffstat (limited to 'arch/mips/sibyte/sb1250/smp.c')
| -rw-r--r-- | arch/mips/sibyte/sb1250/smp.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/arch/mips/sibyte/sb1250/smp.c b/arch/mips/sibyte/sb1250/smp.c new file mode 100644 index 0000000000..7a794234e3 --- /dev/null +++ b/arch/mips/sibyte/sb1250/smp.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2001, 2002, 2003 Broadcom Corporation + */ + +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/smp.h> +#include <linux/kernel_stat.h> +#include <linux/sched/task_stack.h> + +#include <asm/mmu_context.h> +#include <asm/io.h> +#include <asm/fw/cfe/cfe_api.h> +#include <asm/sibyte/sb1250.h> +#include <asm/sibyte/sb1250_regs.h> +#include <asm/sibyte/sb1250_int.h> + +static void *mailbox_set_regs[] = { + IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_SET_CPU), + IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_SET_CPU) +}; + +static void *mailbox_clear_regs[] = { + IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CLR_CPU), + IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CLR_CPU) +}; + +static void *mailbox_regs[] = { + IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CPU), + IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CPU) +}; + +/* + * SMP init and finish on secondary CPUs + */ +void sb1250_smp_init(void) +{ + unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 | + STATUSF_IP1 | STATUSF_IP0; + + /* Set interrupt mask, but don't enable */ + change_c0_status(ST0_IM, imask); +} + +/* + * These are routines for dealing with the sb1250 smp capabilities + * independent of board/firmware + */ + +/* + * Simple enough; everything is set up, so just poke the appropriate mailbox + * register, and we should be set + */ +static void sb1250_send_ipi_single(int cpu, unsigned int action) +{ + __raw_writeq((((u64)action) << 48), mailbox_set_regs[cpu]); +} + +static inline void sb1250_send_ipi_mask(const struct cpumask *mask, + unsigned int action) +{ + unsigned int i; + + for_each_cpu(i, mask) + sb1250_send_ipi_single(i, action); +} + +/* + * Code to run on secondary just after probing the CPU + */ +static void sb1250_init_secondary(void) +{ + extern void sb1250_smp_init(void); + + sb1250_smp_init(); +} + +/* + * Do any tidying up before marking online and running the idle + * loop + */ +static void sb1250_smp_finish(void) +{ + extern void sb1250_clockevent_init(void); + + sb1250_clockevent_init(); + local_irq_enable(); +} + +/* + * Setup the PC, SP, and GP of a secondary processor and start it + * running! + */ +static int sb1250_boot_secondary(int cpu, struct task_struct *idle) +{ + int retval; + + retval = cfe_cpu_start(cpu_logical_map(cpu), &smp_bootstrap, + __KSTK_TOS(idle), + (unsigned long)task_thread_info(idle), 0); + if (retval != 0) + printk("cfe_start_cpu(%i) returned %i\n" , cpu, retval); + return retval; +} + +/* + * Use CFE to find out how many CPUs are available, setting up + * cpu_possible_mask and the logical/physical mappings. + * XXXKW will the boot CPU ever not be physical 0? + * + * Common setup before any secondaries are started + */ +static void __init sb1250_smp_setup(void) +{ + int i, num; + + init_cpu_possible(cpumask_of(0)); + __cpu_number_map[0] = 0; + __cpu_logical_map[0] = 0; + + for (i = 1, num = 0; i < NR_CPUS; i++) { + if (cfe_cpu_stop(i) == 0) { + set_cpu_possible(i, true); + __cpu_number_map[i] = ++num; + __cpu_logical_map[num] = i; + } + } + printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num); +} + +static void __init sb1250_prepare_cpus(unsigned int max_cpus) +{ +} + +const struct plat_smp_ops sb_smp_ops = { + .send_ipi_single = sb1250_send_ipi_single, + .send_ipi_mask = sb1250_send_ipi_mask, + .init_secondary = sb1250_init_secondary, + .smp_finish = sb1250_smp_finish, + .boot_secondary = sb1250_boot_secondary, + .smp_setup = sb1250_smp_setup, + .prepare_cpus = sb1250_prepare_cpus, +}; + +void sb1250_mailbox_interrupt(void) +{ + int cpu = smp_processor_id(); + int irq = K_INT_MBOX_0; + unsigned int action; + + kstat_incr_irq_this_cpu(irq); + /* Load the mailbox register to figure out what we're supposed to do */ + action = (____raw_readq(mailbox_regs[cpu]) >> 48) & 0xffff; + + /* Clear the mailbox to clear the interrupt */ + ____raw_writeq(((u64)action) << 48, mailbox_clear_regs[cpu]); + + if (action & SMP_RESCHEDULE_YOURSELF) + scheduler_ipi(); + + if (action & SMP_CALL_FUNCTION) { + irq_enter(); + generic_smp_call_function_interrupt(); + irq_exit(); + } +} |