Virtual SMP support for the 34K.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/smp_mt.c b/arch/mips/kernel/smp_mt.c
new file mode 100644
index 0000000..d429544
--- /dev/null
+++ b/arch/mips/kernel/smp_mt.c
@@ -0,0 +1,366 @@
+/*
+ * Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved.
+ *
+ * Elizabeth Clarke (beth@mips.com)
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+#include <linux/compiler.h>
+
+#include <asm/atomic.h>
+#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/hardirq.h>
+#include <asm/mmu_context.h>
+#include <asm/smp.h>
+#include <asm/time.h>
+#include <asm/mipsregs.h>
+#include <asm/mipsmtregs.h>
+#include <asm/cacheflush.h>
+#include <asm/mips-boards/maltaint.h>
+
+#define MIPS_CPU_IPI_RESCHED_IRQ 0
+#define MIPS_CPU_IPI_CALL_IRQ 1
+
+static int cpu_ipi_resched_irq, cpu_ipi_call_irq;
+
+#if 0
+static void dump_mtregisters(int vpe, int tc)
+{
+ printk("vpe %d tc %d\n", vpe, tc);
+
+ settc(tc);
+
+ printk(" c0 status 0x%lx\n", read_vpe_c0_status());
+ printk(" vpecontrol 0x%lx\n", read_vpe_c0_vpecontrol());
+ printk(" vpeconf0 0x%lx\n", read_vpe_c0_vpeconf0());
+ printk(" tcstatus 0x%lx\n", read_tc_c0_tcstatus());
+ printk(" tcrestart 0x%lx\n", read_tc_c0_tcrestart());
+ printk(" tcbind 0x%lx\n", read_tc_c0_tcbind());
+ printk(" tchalt 0x%lx\n", read_tc_c0_tchalt());
+}
+#endif
+
+void __init sanitize_tlb_entries(void)
+{
+ int i, tlbsiz;
+ unsigned long mvpconf0, ncpu;
+
+ if (!cpu_has_mipsmt)
+ return;
+
+ set_c0_mvpcontrol(MVPCONTROL_VPC);
+
+ /* Disable TLB sharing */
+ clear_c0_mvpcontrol(MVPCONTROL_STLB);
+
+ mvpconf0 = read_c0_mvpconf0();
+
+ printk(KERN_INFO "MVPConf0 0x%lx TLBS %lx PTLBE %ld\n", mvpconf0,
+ (mvpconf0 & MVPCONF0_TLBS) >> MVPCONF0_TLBS_SHIFT,
+ (mvpconf0 & MVPCONF0_PTLBE) >> MVPCONF0_PTLBE_SHIFT);
+
+ tlbsiz = (mvpconf0 & MVPCONF0_PTLBE) >> MVPCONF0_PTLBE_SHIFT;
+ ncpu = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
+
+ printk(" tlbsiz %d ncpu %ld\n", tlbsiz, ncpu);
+
+ if (tlbsiz > 0) {
+ /* share them out across the vpe's */
+ tlbsiz /= ncpu;
+
+ printk(KERN_INFO "setting Config1.MMU_size to %d\n", tlbsiz);
+
+ for (i = 0; i < ncpu; i++) {
+ settc(i);
+
+ if (i == 0)
+ write_c0_config1((read_c0_config1() & ~(0x3f << 25)) | (tlbsiz << 25));
+ else
+ write_vpe_c0_config1((read_vpe_c0_config1() & ~(0x3f << 25)) |
+ (tlbsiz << 25));
+ }
+ }
+
+ clear_c0_mvpcontrol(MVPCONTROL_VPC);
+}
+
+#if 0
+/*
+ * Use c0_MVPConf0 to find out how many CPUs are available, setting up
+ * phys_cpu_present_map and the logical/physical mappings.
+ */
+void __init prom_build_cpu_map(void)
+{
+ int i, num, ncpus;
+
+ cpus_clear(phys_cpu_present_map);
+
+ /* assume we boot on cpu 0.... */
+ cpu_set(0, phys_cpu_present_map);
+ __cpu_number_map[0] = 0;
+ __cpu_logical_map[0] = 0;
+
+ if (cpu_has_mipsmt) {
+ ncpus = ((read_c0_mvpconf0() & (MVPCONF0_PVPE)) >> MVPCONF0_PVPE_SHIFT) + 1;
+ for (i=1, num=0; i< NR_CPUS && i<ncpus; i++) {
+ cpu_set(i, phys_cpu_present_map);
+ __cpu_number_map[i] = ++num;
+ __cpu_logical_map[num] = i;
+ }
+
+ printk(KERN_INFO "%i available secondary CPU(s)\n", num);
+ }
+}
+#endif
+
+static void ipi_resched_dispatch (struct pt_regs *regs)
+{
+ do_IRQ(MIPS_CPU_IPI_RESCHED_IRQ, regs);
+}
+
+static void ipi_call_dispatch (struct pt_regs *regs)
+{
+ do_IRQ(MIPS_CPU_IPI_CALL_IRQ, regs);
+}
+
+irqreturn_t ipi_resched_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ return IRQ_HANDLED;
+}
+
+irqreturn_t ipi_call_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ smp_call_function_interrupt();
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction irq_resched = {
+ .handler = ipi_resched_interrupt,
+ .flags = SA_INTERRUPT,
+ .name = "IPI_resched"
+};
+
+static struct irqaction irq_call = {
+ .handler = ipi_call_interrupt,
+ .flags = SA_INTERRUPT,
+ .name = "IPI_call"
+};
+
+/*
+ * Common setup before any secondaries are started
+ * Make sure all CPU's are in a sensible state before we boot any of the
+ * secondarys
+ */
+void prom_prepare_cpus(unsigned int max_cpus)
+{
+ unsigned long val;
+ int i, num;
+
+ if (!cpu_has_mipsmt)
+ return;
+
+ /* disable MT so we can configure */
+ dvpe();
+ dmt();
+
+ /* Put MVPE's into 'configuration state' */
+ set_c0_mvpcontrol(MVPCONTROL_VPC);
+
+ val = read_c0_mvpconf0();
+
+ /* we'll always have more TC's than VPE's, so loop setting everything
+ to a sensible state */
+ for (i = 0, num = 0; i <= ((val & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT); i++) {
+ settc(i);
+
+ /* VPE's */
+ if (i <= ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT)) {
+
+ /* deactivate all but vpe0 */
+ if (i != 0) {
+ unsigned long tmp = read_vpe_c0_vpeconf0();
+
+ tmp &= ~VPECONF0_VPA;
+
+ /* master VPE */
+ tmp |= VPECONF0_MVP;
+ write_vpe_c0_vpeconf0(tmp);
+
+ /* Record this as available CPU */
+ if (i < max_cpus) {
+ cpu_set(i, phys_cpu_present_map);
+ __cpu_number_map[i] = ++num;
+ __cpu_logical_map[num] = i;
+ }
+ }
+
+ /* disable multi-threading with TC's */
+ write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
+
+ if (i != 0) {
+ write_vpe_c0_status((read_c0_status() & ~(ST0_IM | ST0_IE | ST0_KSU)) | ST0_CU0);
+ write_vpe_c0_cause(read_vpe_c0_cause() & ~CAUSEF_IP);
+
+ /* set config to be the same as vpe0, particularly kseg0 coherency alg */
+ write_vpe_c0_config( read_c0_config());
+ }
+
+ }
+
+ /* TC's */
+
+ if (i != 0) {
+ unsigned long tmp;
+
+ /* bind a TC to each VPE, May as well put all excess TC's
+ on the last VPE */
+ if ( i >= (((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT)+1) )
+ write_tc_c0_tcbind(read_tc_c0_tcbind() | ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) );
+ else {
+ write_tc_c0_tcbind( read_tc_c0_tcbind() | i);
+
+ /* and set XTC */
+ write_vpe_c0_vpeconf0( read_vpe_c0_vpeconf0() | (i << VPECONF0_XTC_SHIFT));
+ }
+
+ tmp = read_tc_c0_tcstatus();
+
+ /* mark not allocated and not dynamically allocatable */
+ tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
+ tmp |= TCSTATUS_IXMT; /* interrupt exempt */
+ write_tc_c0_tcstatus(tmp);
+
+ write_tc_c0_tchalt(TCHALT_H);
+ }
+ }
+
+ /* Release config state */
+ clear_c0_mvpcontrol(MVPCONTROL_VPC);
+
+ /* We'll wait until starting the secondaries before starting MVPE */
+
+ printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num);
+
+ /* set up ipi interrupts */
+ if (cpu_has_vint) {
+ set_vi_handler (MIPS_CPU_IPI_RESCHED_IRQ, ipi_resched_dispatch);
+ set_vi_handler (MIPS_CPU_IPI_CALL_IRQ, ipi_call_dispatch);
+ }
+
+ cpu_ipi_resched_irq = MIPSCPU_INT_BASE + MIPS_CPU_IPI_RESCHED_IRQ;
+ cpu_ipi_call_irq = MIPSCPU_INT_BASE + MIPS_CPU_IPI_CALL_IRQ;
+
+ setup_irq(cpu_ipi_resched_irq, &irq_resched);
+ setup_irq(cpu_ipi_call_irq, &irq_call);
+
+ /* need to mark IPI's as IRQ_PER_CPU */
+ irq_desc[cpu_ipi_resched_irq].status |= IRQ_PER_CPU;
+ irq_desc[cpu_ipi_call_irq].status |= IRQ_PER_CPU;
+}
+
+/*
+ * Setup the PC, SP, and GP of a secondary processor and start it
+ * running!
+ * smp_bootstrap is the place to resume from
+ * __KSTK_TOS(idle) is apparently the stack pointer
+ * (unsigned long)idle->thread_info the gp
+ * assumes a 1:1 mapping of TC => VPE
+ */
+void prom_boot_secondary(int cpu, struct task_struct *idle)
+{
+ dvpe();
+ set_c0_mvpcontrol(MVPCONTROL_VPC);
+
+ settc(cpu);
+
+ /* restart */
+ write_tc_c0_tcrestart((unsigned long)&smp_bootstrap);
+
+ /* enable the tc this vpe/cpu will be running */
+ write_tc_c0_tcstatus((read_tc_c0_tcstatus() & ~TCSTATUS_IXMT) | TCSTATUS_A);
+
+ write_tc_c0_tchalt(0);
+
+ /* enable the VPE */
+ write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
+
+ /* stack pointer */
+ write_tc_gpr_sp( __KSTK_TOS(idle));
+
+ /* global pointer */
+ write_tc_gpr_gp((unsigned long)idle->thread_info);
+
+ flush_icache_range((unsigned long)idle->thread_info,
+ (unsigned long)idle->thread_info +
+ sizeof(struct thread_info));
+
+ /* finally out of configuration and into chaos */
+ clear_c0_mvpcontrol(MVPCONTROL_VPC);
+
+ evpe(EVPE_ENABLE);
+}
+
+void prom_init_secondary(void)
+{
+ write_c0_status((read_c0_status() & ~ST0_IM ) |
+ (STATUSF_IP0 | STATUSF_IP1 | STATUSF_IP7));
+}
+
+void prom_smp_finish(void)
+{
+ write_c0_compare(read_c0_count() + (8* mips_hpt_frequency/HZ));
+
+ local_irq_enable();
+}
+
+void prom_cpus_done(void)
+{
+}
+
+void core_send_ipi(int cpu, unsigned int action)
+{
+ int i;
+ unsigned long flags;
+ int vpflags;
+
+ local_irq_save (flags);
+
+ vpflags = dvpe(); /* cant access the other CPU's registers whilst MVPE enabled */
+
+ switch (action) {
+ case SMP_CALL_FUNCTION:
+ i = C_SW1;
+ break;
+
+ case SMP_RESCHEDULE_YOURSELF:
+ default:
+ i = C_SW0;
+ break;
+ }
+
+ /* 1:1 mapping of vpe and tc... */
+ settc(cpu);
+ write_vpe_c0_cause(read_vpe_c0_cause() | i);
+ evpe(vpflags);
+
+ local_irq_restore(flags);
+}