MIPS: Cavium: Add CPU hotplugging code.
Thanks to Cavium Inc. for the code contribution and help.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/cavium-octeon/smp.c b/arch/mips/cavium-octeon/smp.c
index 24e0ad6..0b891a9 100644
--- a/arch/mips/cavium-octeon/smp.c
+++ b/arch/mips/cavium-octeon/smp.c
@@ -5,6 +5,7 @@
*
* Copyright (C) 2004-2008 Cavium Networks
*/
+#include <linux/cpu.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/smp.h>
@@ -19,10 +20,16 @@
#include <asm/octeon/octeon.h>
+#include "octeon_boot.h"
+
volatile unsigned long octeon_processor_boot = 0xff;
volatile unsigned long octeon_processor_sp;
volatile unsigned long octeon_processor_gp;
+#ifdef CONFIG_HOTPLUG_CPU
+static unsigned int InitTLBStart_addr;
+#endif
+
static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
{
const int coreid = cvmx_get_core_num();
@@ -67,8 +74,28 @@
}
/**
- * Detect available CPUs, populate phys_cpu_present_map
+ * Detect available CPUs, populate cpu_possible_map
*/
+static void octeon_smp_hotplug_setup(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ uint32_t labi_signature;
+
+ labi_signature =
+ cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ LABI_ADDR_IN_BOOTLOADER +
+ offsetof(struct linux_app_boot_info,
+ labi_signature)));
+ if (labi_signature != LABI_SIGNATURE)
+ pr_err("The bootloader version on this board is incorrect\n");
+ InitTLBStart_addr =
+ cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ LABI_ADDR_IN_BOOTLOADER +
+ offsetof(struct linux_app_boot_info,
+ InitTLBStart_addr)));
+#endif
+}
+
static void octeon_smp_setup(void)
{
const int coreid = cvmx_get_core_num();
@@ -91,6 +118,9 @@
cpus++;
}
}
+ cpu_present_map = cpu_possible_map;
+
+ octeon_smp_hotplug_setup();
}
/**
@@ -128,6 +158,17 @@
const int coreid = cvmx_get_core_num();
union cvmx_ciu_intx_sum0 interrupt_enable;
+#ifdef CONFIG_HOTPLUG_CPU
+ unsigned int cur_exception_base;
+
+ cur_exception_base = cvmx_read64_uint32(
+ CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ LABI_ADDR_IN_BOOTLOADER +
+ offsetof(struct linux_app_boot_info,
+ cur_exception_base)));
+ /* cur_exception_base is incremented in bootloader after setting */
+ write_c0_ebase((unsigned int)(cur_exception_base - EXCEPTION_BASE_INCR));
+#endif
octeon_check_cpu_bist();
octeon_init_cvmcount();
/*
@@ -199,6 +240,193 @@
#endif
}
+#ifdef CONFIG_HOTPLUG_CPU
+
+/* State of each CPU. */
+DEFINE_PER_CPU(int, cpu_state);
+
+extern void fixup_irqs(void);
+
+static DEFINE_SPINLOCK(smp_reserve_lock);
+
+static int octeon_cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+
+ if (cpu == 0)
+ return -EBUSY;
+
+ spin_lock(&smp_reserve_lock);
+
+ cpu_clear(cpu, cpu_online_map);
+ cpu_clear(cpu, cpu_callin_map);
+ local_irq_disable();
+ fixup_irqs();
+ local_irq_enable();
+
+ flush_cache_all();
+ local_flush_tlb_all();
+
+ spin_unlock(&smp_reserve_lock);
+
+ return 0;
+}
+
+static void octeon_cpu_die(unsigned int cpu)
+{
+ int coreid = cpu_logical_map(cpu);
+ uint32_t avail_coremask;
+ struct cvmx_bootmem_named_block_desc *block_desc;
+
+#ifdef CONFIG_CAVIUM_OCTEON_WATCHDOG
+ /* Disable the watchdog */
+ cvmx_ciu_wdogx_t ciu_wdog;
+ ciu_wdog.u64 = cvmx_read_csr(CVMX_CIU_WDOGX(cpu));
+ ciu_wdog.s.mode = 0;
+ cvmx_write_csr(CVMX_CIU_WDOGX(cpu), ciu_wdog.u64);
+#endif
+
+ while (per_cpu(cpu_state, cpu) != CPU_DEAD)
+ cpu_relax();
+
+ /*
+ * This is a bit complicated strategics of getting/settig available
+ * cores mask, copied from bootloader
+ */
+ /* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
+ block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
+
+ if (!block_desc) {
+ avail_coremask =
+ cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ LABI_ADDR_IN_BOOTLOADER +
+ offsetof
+ (struct linux_app_boot_info,
+ avail_coremask)));
+ } else { /* alternative, already initialized */
+ avail_coremask =
+ cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ block_desc->base_addr +
+ AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK));
+ }
+
+ avail_coremask |= 1 << coreid;
+
+ /* Setting avail_coremask for bootoct binary */
+ if (!block_desc) {
+ cvmx_write64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ LABI_ADDR_IN_BOOTLOADER +
+ offsetof(struct linux_app_boot_info,
+ avail_coremask)),
+ avail_coremask);
+ } else {
+ cvmx_write64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ block_desc->base_addr +
+ AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK),
+ avail_coremask);
+ }
+
+ pr_info("Reset core %d. Available Coremask = %x \n", coreid,
+ avail_coremask);
+ cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
+ cvmx_write_csr(CVMX_CIU_PP_RST, 0);
+}
+
+void play_dead(void)
+{
+ int coreid = cvmx_get_core_num();
+
+ idle_task_exit();
+ octeon_processor_boot = 0xff;
+ per_cpu(cpu_state, coreid) = CPU_DEAD;
+
+ while (1) /* core will be reset here */
+ ;
+}
+
+extern void kernel_entry(unsigned long arg1, ...);
+
+static void start_after_reset(void)
+{
+ kernel_entry(0, 0, 0); /* set a2 = 0 for secondary core */
+}
+
+int octeon_update_boot_vector(unsigned int cpu)
+{
+
+ int coreid = cpu_logical_map(cpu);
+ unsigned int avail_coremask;
+ struct cvmx_bootmem_named_block_desc *block_desc;
+ struct boot_init_vector *boot_vect =
+ (struct boot_init_vector *) cvmx_phys_to_ptr(0x0 +
+ BOOTLOADER_BOOT_VECTOR);
+
+ block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
+
+ if (!block_desc) {
+ avail_coremask =
+ cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ LABI_ADDR_IN_BOOTLOADER +
+ offsetof(struct linux_app_boot_info,
+ avail_coremask)));
+ } else { /* alternative, already initialized */
+ avail_coremask =
+ cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
+ block_desc->base_addr +
+ AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK));
+ }
+
+ if (!(avail_coremask & (1 << coreid))) {
+ /* core not available, assume, that catched by simple-executive */
+ cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
+ cvmx_write_csr(CVMX_CIU_PP_RST, 0);
+ }
+
+ boot_vect[coreid].app_start_func_addr =
+ (uint32_t) (unsigned long) start_after_reset;
+ boot_vect[coreid].code_addr = InitTLBStart_addr;
+
+ CVMX_SYNC;
+
+ cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
+
+ return 0;
+}
+
+static int __cpuinit octeon_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+
+ switch (action) {
+ case CPU_UP_PREPARE:
+ octeon_update_boot_vector(cpu);
+ break;
+ case CPU_ONLINE:
+ pr_info("Cpu %d online\n", cpu);
+ break;
+ case CPU_DEAD:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata octeon_cpu_notifier = {
+ .notifier_call = octeon_cpu_callback,
+};
+
+static int __cpuinit register_cavium_notifier(void)
+{
+ register_hotcpu_notifier(&octeon_cpu_notifier);
+
+ return 0;
+}
+
+late_initcall(register_cavium_notifier);
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
struct plat_smp_ops octeon_smp_ops = {
.send_ipi_single = octeon_send_ipi_single,
.send_ipi_mask = octeon_send_ipi_mask,
@@ -208,4 +436,8 @@
.boot_secondary = octeon_boot_secondary,
.smp_setup = octeon_smp_setup,
.prepare_cpus = octeon_prepare_cpus,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_disable = octeon_cpu_disable,
+ .cpu_die = octeon_cpu_die,
+#endif
};