diff options
Diffstat (limited to 'arch/sparc/kernel/leon_smp.c')
-rw-r--r-- | arch/sparc/kernel/leon_smp.c | 468 |
1 files changed, 468 insertions, 0 deletions
diff --git a/arch/sparc/kernel/leon_smp.c b/arch/sparc/kernel/leon_smp.c new file mode 100644 index 000000000..1eed26d42 --- /dev/null +++ b/arch/sparc/kernel/leon_smp.c @@ -0,0 +1,468 @@ +// SPDX-License-Identifier: GPL-2.0 +/* leon_smp.c: Sparc-Leon SMP support. + * + * based on sun4m_smp.c + * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) + * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB + * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB + */ + +#include <asm/head.h> + +#include <linux/kernel.h> +#include <linux/sched/mm.h> +#include <linux/threads.h> +#include <linux/smp.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/of.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/profile.h> +#include <linux/pm.h> +#include <linux/delay.h> +#include <linux/gfp.h> +#include <linux/cpu.h> +#include <linux/clockchips.h> + +#include <asm/cacheflush.h> +#include <asm/tlbflush.h> + +#include <asm/ptrace.h> +#include <linux/atomic.h> +#include <asm/irq_regs.h> +#include <asm/traps.h> + +#include <asm/delay.h> +#include <asm/irq.h> +#include <asm/page.h> +#include <asm/oplib.h> +#include <asm/cpudata.h> +#include <asm/asi.h> +#include <asm/leon.h> +#include <asm/leon_amba.h> +#include <asm/timer.h> + +#include "kernel.h" + +#include "irq.h" + +extern ctxd_t *srmmu_ctx_table_phys; +static int smp_processors_ready; +extern volatile unsigned long cpu_callin_map[NR_CPUS]; +extern cpumask_t smp_commenced_mask; +void leon_configure_cache_smp(void); +static void leon_ipi_init(void); + +/* IRQ number of LEON IPIs */ +int leon_ipi_irq = LEON3_IRQ_IPI_DEFAULT; + +static inline unsigned long do_swap(volatile unsigned long *ptr, + unsigned long val) +{ + __asm__ __volatile__("swapa [%2] %3, %0\n\t" : "=&r"(val) + : "0"(val), "r"(ptr), "i"(ASI_LEON_DCACHE_MISS) + : "memory"); + return val; +} + +void leon_cpu_pre_starting(void *arg) +{ + leon_configure_cache_smp(); +} + +void leon_cpu_pre_online(void *arg) +{ + int cpuid = hard_smp_processor_id(); + + /* Allow master to continue. The master will then give us the + * go-ahead by setting the smp_commenced_mask and will wait without + * timeouts until our setup is completed fully (signified by + * our bit being set in the cpu_online_mask). + */ + do_swap(&cpu_callin_map[cpuid], 1); + + local_ops->cache_all(); + local_ops->tlb_all(); + + /* Fix idle thread fields. */ + __asm__ __volatile__("ld [%0], %%g6\n\t" : : "r"(¤t_set[cpuid]) + : "memory" /* paranoid */); + + /* Attach to the address space of init_task. */ + mmgrab(&init_mm); + current->active_mm = &init_mm; + + while (!cpumask_test_cpu(cpuid, &smp_commenced_mask)) + mb(); +} + +/* + * Cycle through the processors asking the PROM to start each one. + */ + +extern struct linux_prom_registers smp_penguin_ctable; + +void leon_configure_cache_smp(void) +{ + unsigned long cfg = sparc_leon3_get_dcachecfg(); + int me = smp_processor_id(); + + if (ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg) > 4) { + printk(KERN_INFO "Note: SMP with snooping only works on 4k cache, found %dk(0x%x) on cpu %d, disabling caches\n", + (unsigned int)ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg), + (unsigned int)cfg, (unsigned int)me); + sparc_leon3_disable_cache(); + } else { + if (cfg & ASI_LEON3_SYSCTRL_CFG_SNOOPING) { + sparc_leon3_enable_snooping(); + } else { + printk(KERN_INFO "Note: You have to enable snooping in the vhdl model cpu %d, disabling caches\n", + me); + sparc_leon3_disable_cache(); + } + } + + local_ops->cache_all(); + local_ops->tlb_all(); +} + +static void leon_smp_setbroadcast(unsigned int mask) +{ + int broadcast = + ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >> + LEON3_IRQMPSTATUS_BROADCAST) & 1); + if (!broadcast) { + prom_printf("######## !!!! The irqmp-ctrl must have broadcast enabled, smp wont work !!!!! ####### nr cpus: %d\n", + leon_smp_nrcpus()); + if (leon_smp_nrcpus() > 1) { + BUG(); + } else { + prom_printf("continue anyway\n"); + return; + } + } + LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpbroadcast), mask); +} + +int leon_smp_nrcpus(void) +{ + int nrcpu = + ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >> + LEON3_IRQMPSTATUS_CPUNR) & 0xf) + 1; + return nrcpu; +} + +void __init leon_boot_cpus(void) +{ + int nrcpu = leon_smp_nrcpus(); + int me = smp_processor_id(); + + /* Setup IPI */ + leon_ipi_init(); + + printk(KERN_INFO "%d:(%d:%d) cpus mpirq at 0x%x\n", (unsigned int)me, + (unsigned int)nrcpu, (unsigned int)NR_CPUS, + (unsigned int)&(leon3_irqctrl_regs->mpstatus)); + + leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, me); + leon_enable_irq_cpu(LEON3_IRQ_TICKER, me); + leon_enable_irq_cpu(leon_ipi_irq, me); + + leon_smp_setbroadcast(1 << LEON3_IRQ_TICKER); + + leon_configure_cache_smp(); + local_ops->cache_all(); + +} + +int leon_boot_one_cpu(int i, struct task_struct *idle) +{ + int timeout; + + current_set[i] = task_thread_info(idle); + + /* See trampoline.S:leon_smp_cpu_startup for details... + * Initialize the contexts table + * Since the call to prom_startcpu() trashes the structure, + * we need to re-initialize it for each cpu + */ + smp_penguin_ctable.which_io = 0; + smp_penguin_ctable.phys_addr = (unsigned int)srmmu_ctx_table_phys; + smp_penguin_ctable.reg_size = 0; + + /* whirrr, whirrr, whirrrrrrrrr... */ + printk(KERN_INFO "Starting CPU %d : (irqmp: 0x%x)\n", (unsigned int)i, + (unsigned int)&leon3_irqctrl_regs->mpstatus); + local_ops->cache_all(); + + /* Make sure all IRQs are of from the start for this new CPU */ + LEON_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[i], 0); + + /* Wake one CPU */ + LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpstatus), 1 << i); + + /* wheee... it's going... */ + for (timeout = 0; timeout < 10000; timeout++) { + if (cpu_callin_map[i]) + break; + udelay(200); + } + printk(KERN_INFO "Started CPU %d\n", (unsigned int)i); + + if (!(cpu_callin_map[i])) { + printk(KERN_ERR "Processor %d is stuck.\n", i); + return -ENODEV; + } else { + leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, i); + leon_enable_irq_cpu(LEON3_IRQ_TICKER, i); + leon_enable_irq_cpu(leon_ipi_irq, i); + } + + local_ops->cache_all(); + return 0; +} + +void __init leon_smp_done(void) +{ + + int i, first; + int *prev; + + /* setup cpu list for irq rotation */ + first = 0; + prev = &first; + for (i = 0; i < NR_CPUS; i++) { + if (cpu_online(i)) { + *prev = i; + prev = &cpu_data(i).next; + } + } + *prev = first; + local_ops->cache_all(); + + /* Free unneeded trap tables */ + if (!cpu_present(1)) { + free_reserved_page(virt_to_page(&trapbase_cpu1)); + } + if (!cpu_present(2)) { + free_reserved_page(virt_to_page(&trapbase_cpu2)); + } + if (!cpu_present(3)) { + free_reserved_page(virt_to_page(&trapbase_cpu3)); + } + /* Ok, they are spinning and ready to go. */ + smp_processors_ready = 1; + +} + +struct leon_ipi_work { + int single; + int msk; + int resched; +}; + +static DEFINE_PER_CPU_SHARED_ALIGNED(struct leon_ipi_work, leon_ipi_work); + +/* Initialize IPIs on the LEON, in order to save IRQ resources only one IRQ + * is used for all three types of IPIs. + */ +static void __init leon_ipi_init(void) +{ + int cpu, len; + struct leon_ipi_work *work; + struct property *pp; + struct device_node *rootnp; + struct tt_entry *trap_table; + unsigned long flags; + + /* Find IPI IRQ or stick with default value */ + rootnp = of_find_node_by_path("/ambapp0"); + if (rootnp) { + pp = of_find_property(rootnp, "ipi_num", &len); + if (pp && (*(int *)pp->value)) + leon_ipi_irq = *(int *)pp->value; + } + printk(KERN_INFO "leon: SMP IPIs at IRQ %d\n", leon_ipi_irq); + + /* Adjust so that we jump directly to smpleon_ipi */ + local_irq_save(flags); + trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (leon_ipi_irq - 1)]; + trap_table->inst_three += smpleon_ipi - real_irq_entry; + local_ops->cache_all(); + local_irq_restore(flags); + + for_each_possible_cpu(cpu) { + work = &per_cpu(leon_ipi_work, cpu); + work->single = work->msk = work->resched = 0; + } +} + +static void leon_send_ipi(int cpu, int level) +{ + unsigned long mask; + mask = leon_get_irqmask(level); + LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->force[cpu], mask); +} + +static void leon_ipi_single(int cpu) +{ + struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu); + + /* Mark work */ + work->single = 1; + + /* Generate IRQ on the CPU */ + leon_send_ipi(cpu, leon_ipi_irq); +} + +static void leon_ipi_mask_one(int cpu) +{ + struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu); + + /* Mark work */ + work->msk = 1; + + /* Generate IRQ on the CPU */ + leon_send_ipi(cpu, leon_ipi_irq); +} + +static void leon_ipi_resched(int cpu) +{ + struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu); + + /* Mark work */ + work->resched = 1; + + /* Generate IRQ on the CPU (any IRQ will cause resched) */ + leon_send_ipi(cpu, leon_ipi_irq); +} + +void leonsmp_ipi_interrupt(void) +{ + struct leon_ipi_work *work = this_cpu_ptr(&leon_ipi_work); + + if (work->single) { + work->single = 0; + smp_call_function_single_interrupt(); + } + if (work->msk) { + work->msk = 0; + smp_call_function_interrupt(); + } + if (work->resched) { + work->resched = 0; + smp_resched_interrupt(); + } +} + +static struct smp_funcall { + smpfunc_t func; + unsigned long arg1; + unsigned long arg2; + unsigned long arg3; + unsigned long arg4; + unsigned long arg5; + unsigned long processors_in[NR_CPUS]; /* Set when ipi entered. */ + unsigned long processors_out[NR_CPUS]; /* Set when ipi exited. */ +} ccall_info __attribute__((aligned(8))); + +static DEFINE_SPINLOCK(cross_call_lock); + +/* Cross calls must be serialized, at least currently. */ +static void leon_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1, + unsigned long arg2, unsigned long arg3, + unsigned long arg4) +{ + if (smp_processors_ready) { + register int high = NR_CPUS - 1; + unsigned long flags; + + spin_lock_irqsave(&cross_call_lock, flags); + + { + /* If you make changes here, make sure gcc generates proper code... */ + register smpfunc_t f asm("i0") = func; + register unsigned long a1 asm("i1") = arg1; + register unsigned long a2 asm("i2") = arg2; + register unsigned long a3 asm("i3") = arg3; + register unsigned long a4 asm("i4") = arg4; + register unsigned long a5 asm("i5") = 0; + + __asm__ __volatile__("std %0, [%6]\n\t" + "std %2, [%6 + 8]\n\t" + "std %4, [%6 + 16]\n\t" : : + "r"(f), "r"(a1), "r"(a2), "r"(a3), + "r"(a4), "r"(a5), + "r"(&ccall_info.func)); + } + + /* Init receive/complete mapping, plus fire the IPI's off. */ + { + register int i; + + cpumask_clear_cpu(smp_processor_id(), &mask); + cpumask_and(&mask, cpu_online_mask, &mask); + for (i = 0; i <= high; i++) { + if (cpumask_test_cpu(i, &mask)) { + ccall_info.processors_in[i] = 0; + ccall_info.processors_out[i] = 0; + leon_send_ipi(i, LEON3_IRQ_CROSS_CALL); + + } + } + } + + { + register int i; + + i = 0; + do { + if (!cpumask_test_cpu(i, &mask)) + continue; + + while (!ccall_info.processors_in[i]) + barrier(); + } while (++i <= high); + + i = 0; + do { + if (!cpumask_test_cpu(i, &mask)) + continue; + + while (!ccall_info.processors_out[i]) + barrier(); + } while (++i <= high); + } + + spin_unlock_irqrestore(&cross_call_lock, flags); + } +} + +/* Running cross calls. */ +void leon_cross_call_irq(void) +{ + int i = smp_processor_id(); + + ccall_info.processors_in[i] = 1; + ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3, + ccall_info.arg4, ccall_info.arg5); + ccall_info.processors_out[i] = 1; +} + +static const struct sparc32_ipi_ops leon_ipi_ops = { + .cross_call = leon_cross_call, + .resched = leon_ipi_resched, + .single = leon_ipi_single, + .mask_one = leon_ipi_mask_one, +}; + +void __init leon_init_smp(void) +{ + /* Patch ipi15 trap table */ + t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_leon - linux_trap_ipi15_sun4m); + + sparc32_ipi_ops = &leon_ipi_ops; +} |