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-rw-r--r--arch/arm/Kconfig2
-rw-r--r--arch/arm/mach-realview/Makefile2
-rw-r--r--arch/arm/mach-realview/core.c2
-rw-r--r--arch/arm/mach-realview/hotplug.c138
-rw-r--r--arch/arm/mach-realview/localtimer.c130
-rw-r--r--arch/arm/mach-realview/platsmp.c5
-rw-r--r--include/asm-arm/arch-realview/entry-macro.S11
-rw-r--r--include/asm-arm/arch-realview/irqs.h3
-rw-r--r--include/asm-arm/arch-realview/platform.h5
9 files changed, 293 insertions, 5 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 3bfef0934c9d..ec77721507cb 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -358,7 +358,7 @@ config HOTPLUG_CPU
config LOCAL_TIMERS
bool "Use local timer interrupts"
- depends on SMP && n
+ depends on SMP && REALVIEW_MPCORE
default y
help
Enable support for local timers on SMP platforms, rather then the
diff --git a/arch/arm/mach-realview/Makefile b/arch/arm/mach-realview/Makefile
index 011a85c10627..36e76ba937fc 100644
--- a/arch/arm/mach-realview/Makefile
+++ b/arch/arm/mach-realview/Makefile
@@ -5,3 +5,5 @@
obj-y := core.o clock.o
obj-$(CONFIG_MACH_REALVIEW_EB) += realview_eb.o
obj-$(CONFIG_SMP) += platsmp.o headsmp.o
+obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
+obj-$(CONFIG_LOCAL_TIMERS) += localtimer.o
diff --git a/arch/arm/mach-realview/core.c b/arch/arm/mach-realview/core.c
index 4ea60d8b6e36..e2c6fa23d3cd 100644
--- a/arch/arm/mach-realview/core.c
+++ b/arch/arm/mach-realview/core.c
@@ -550,7 +550,7 @@ static irqreturn_t realview_timer_interrupt(int irq, void *dev_id, struct pt_reg
timer_tick(regs);
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) && !defined(CONFIG_LOCAL_TIMERS)
smp_send_timer();
update_process_times(user_mode(regs));
#endif
diff --git a/arch/arm/mach-realview/hotplug.c b/arch/arm/mach-realview/hotplug.c
new file mode 100644
index 000000000000..09748cbcd10e
--- /dev/null
+++ b/arch/arm/mach-realview/hotplug.c
@@ -0,0 +1,138 @@
+/*
+ * linux/arch/arm/mach-realview/hotplug.c
+ *
+ * Copyright (C) 2002 ARM Ltd.
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/smp.h>
+#include <linux/completion.h>
+
+extern volatile int pen_release;
+
+static DECLARE_COMPLETION(cpu_killed);
+
+static inline void cpu_enter_lowpower(void)
+{
+ unsigned int v;
+
+ asm volatile( "mcr p15, 0, %1, c7, c14, 0\n"
+ " mcr p15, 0, %1, c7, c5, 0\n"
+ " mcr p15, 0, %1, c7, c10, 4\n"
+ /*
+ * Turn off coherency
+ */
+ " mrc p15, 0, %0, c1, c0, 1\n"
+ " bic %0, %0, #0x20\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ " mrc p15, 0, %0, c1, c0, 0\n"
+ " bic %0, %0, #0x04\n"
+ " mcr p15, 0, %0, c1, c0, 0\n"
+ : "=&r" (v)
+ : "r" (0)
+ : "cc");
+}
+
+static inline void cpu_leave_lowpower(void)
+{
+ unsigned int v;
+
+ asm volatile( "mrc p15, 0, %0, c1, c0, 0\n"
+ " orr %0, %0, #0x04\n"
+ " mcr p15, 0, %0, c1, c0, 0\n"
+ " mrc p15, 0, %0, c1, c0, 1\n"
+ " orr %0, %0, #0x20\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ : "=&r" (v)
+ :
+ : "cc");
+}
+
+static inline void platform_do_lowpower(unsigned int cpu)
+{
+ /*
+ * there is no power-control hardware on this platform, so all
+ * we can do is put the core into WFI; this is safe as the calling
+ * code will have already disabled interrupts
+ */
+ for (;;) {
+ /*
+ * here's the WFI
+ */
+ asm(".word 0xe320f003\n"
+ :
+ :
+ : "memory", "cc");
+
+ if (pen_release == cpu) {
+ /*
+ * OK, proper wakeup, we're done
+ */
+ break;
+ }
+
+ /*
+ * getting here, means that we have come out of WFI without
+ * having been woken up - this shouldn't happen
+ *
+ * The trouble is, letting people know about this is not really
+ * possible, since we are currently running incoherently, and
+ * therefore cannot safely call printk() or anything else
+ */
+#ifdef DEBUG
+ printk("CPU%u: spurious wakeup call\n", cpu);
+#endif
+ }
+}
+
+int platform_cpu_kill(unsigned int cpu)
+{
+ return wait_for_completion_timeout(&cpu_killed, 5000);
+}
+
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+void platform_cpu_die(unsigned int cpu)
+{
+#ifdef DEBUG
+ unsigned int this_cpu = hard_smp_processor_id();
+
+ if (cpu != this_cpu) {
+ printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n",
+ this_cpu, cpu);
+ BUG();
+ }
+#endif
+
+ printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
+ complete(&cpu_killed);
+
+ /*
+ * we're ready for shutdown now, so do it
+ */
+ cpu_enter_lowpower();
+ platform_do_lowpower(cpu);
+
+ /*
+ * bring this CPU back into the world of cache
+ * coherency, and then restore interrupts
+ */
+ cpu_leave_lowpower();
+}
+
+int mach_cpu_disable(unsigned int cpu)
+{
+ /*
+ * we don't allow CPU 0 to be shutdown (it is still too special
+ * e.g. clock tick interrupts)
+ */
+ return cpu == 0 ? -EPERM : 0;
+}
diff --git a/arch/arm/mach-realview/localtimer.c b/arch/arm/mach-realview/localtimer.c
new file mode 100644
index 000000000000..5e917e37d095
--- /dev/null
+++ b/arch/arm/mach-realview/localtimer.c
@@ -0,0 +1,130 @@
+/*
+ * linux/arch/arm/mach-realview/localtimer.c
+ *
+ * Copyright (C) 2002 ARM Ltd.
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+
+#include <asm/mach/time.h>
+#include <asm/hardware/arm_twd.h>
+#include <asm/hardware/gic.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include "core.h"
+
+#define TWD_BASE(cpu) (__io_address(REALVIEW_TWD_BASE) + \
+ ((cpu) * REALVIEW_TWD_SIZE))
+
+static unsigned long mpcore_timer_rate;
+
+/*
+ * local_timer_ack: checks for a local timer interrupt.
+ *
+ * If a local timer interrupt has occured, acknowledge and return 1.
+ * Otherwise, return 0.
+ */
+int local_timer_ack(void)
+{
+ void __iomem *base = TWD_BASE(smp_processor_id());
+
+ if (__raw_readl(base + TWD_TIMER_INTSTAT)) {
+ __raw_writel(1, base + TWD_TIMER_INTSTAT);
+ return 1;
+ }
+
+ return 0;
+}
+
+void __cpuinit local_timer_setup(unsigned int cpu)
+{
+ void __iomem *base = TWD_BASE(cpu);
+ unsigned int load, offset;
+ u64 waitjiffies;
+ unsigned int count;
+
+ /*
+ * If this is the first time round, we need to work out how fast
+ * the timer ticks
+ */
+ if (mpcore_timer_rate == 0) {
+ printk("Calibrating local timer... ");
+
+ /* Wait for a tick to start */
+ waitjiffies = get_jiffies_64() + 1;
+
+ while (get_jiffies_64() < waitjiffies)
+ udelay(10);
+
+ /* OK, now the tick has started, let's get the timer going */
+ waitjiffies += 5;
+
+ /* enable, no interrupt or reload */
+ __raw_writel(0x1, base + TWD_TIMER_CONTROL);
+
+ /* maximum value */
+ __raw_writel(0xFFFFFFFFU, base + TWD_TIMER_COUNTER);
+
+ while (get_jiffies_64() < waitjiffies)
+ udelay(10);
+
+ count = __raw_readl(base + TWD_TIMER_COUNTER);
+
+ mpcore_timer_rate = (0xFFFFFFFFU - count) * (HZ / 5);
+
+ printk("%lu.%02luMHz.\n", mpcore_timer_rate / 1000000,
+ (mpcore_timer_rate / 100000) % 100);
+ }
+
+ load = mpcore_timer_rate / HZ;
+
+ __raw_writel(load, base + TWD_TIMER_LOAD);
+ __raw_writel(0x7, base + TWD_TIMER_CONTROL);
+
+ /*
+ * Now maneuver our local tick into the right part of the jiffy.
+ * Start by working out where within the tick our local timer
+ * interrupt should go.
+ */
+ offset = ((mpcore_timer_rate / HZ) / (NR_CPUS + 1)) * (cpu + 1);
+
+ /*
+ * gettimeoffset() will return a number of us since the last tick.
+ * Convert this number of us to a local timer tick count.
+ * Be careful of integer overflow whilst keeping maximum precision.
+ *
+ * with HZ=100 and 1MHz (fpga) ~ 1GHz processor:
+ * load = 1 ~ 10,000
+ * mpcore_timer_rate/10000 = 100 ~ 100,000
+ *
+ * so the multiply value will be less than 10^9 always.
+ */
+ load = (system_timer->offset() * (mpcore_timer_rate / 10000)) / 100;
+
+ /* Add on our offset to get the load value */
+ load = (load + offset) % (mpcore_timer_rate / HZ);
+
+ __raw_writel(load, base + TWD_TIMER_COUNTER);
+
+ /* Make sure our local interrupt controller has this enabled */
+ __raw_writel(1 << IRQ_LOCALTIMER,
+ __io_address(REALVIEW_GIC_DIST_BASE) + GIC_DIST_ENABLE_SET);
+}
+
+/*
+ * take a local timer down
+ */
+void __cpuexit local_timer_stop(unsigned int cpu)
+{
+ __raw_writel(0, TWD_BASE(cpu) + TWD_TIMER_CONTROL);
+}
diff --git a/arch/arm/mach-realview/platsmp.c b/arch/arm/mach-realview/platsmp.c
index 09b35f62247a..0c7d4ac9a7b3 100644
--- a/arch/arm/mach-realview/platsmp.c
+++ b/arch/arm/mach-realview/platsmp.c
@@ -175,6 +175,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
max_cpus = ncores;
/*
+ * Enable the local timer for primary CPU
+ */
+ local_timer_setup(cpu);
+
+ /*
* Initialise the possible/present maps.
* cpu_possible_map describes the set of CPUs which may be present
* cpu_present_map describes the set of CPUs populated
diff --git a/include/asm-arm/arch-realview/entry-macro.S b/include/asm-arm/arch-realview/entry-macro.S
index 4df469bf42e2..6288fad0dc41 100644
--- a/include/asm-arm/arch-realview/entry-macro.S
+++ b/include/asm-arm/arch-realview/entry-macro.S
@@ -61,3 +61,14 @@
strcc \irqstat, [\base, #GIC_CPU_EOI]
cmpcs \irqnr, \irqnr
.endm
+
+ /* As above, this assumes that irqstat and base are preserved.. */
+
+ .macro test_for_ltirq, irqnr, irqstat, base, tmp
+ bic \irqnr, \irqstat, #0x1c00
+ mov \tmp, #0
+ cmp \irqnr, #29
+ moveq \tmp, #1
+ streq \irqstat, [\base, #GIC_CPU_EOI]
+ cmp \tmp, #0
+ .endm
diff --git a/include/asm-arm/arch-realview/irqs.h b/include/asm-arm/arch-realview/irqs.h
index ff376494e5b1..c16223c9588d 100644
--- a/include/asm-arm/arch-realview/irqs.h
+++ b/include/asm-arm/arch-realview/irqs.h
@@ -21,6 +21,9 @@
#include <asm/arch/platform.h>
+#define IRQ_LOCALTIMER 29
+#define IRQ_LOCALWDOG 30
+
/*
* IRQ interrupts definitions are the same the INT definitions
* held within platform.h
diff --git a/include/asm-arm/arch-realview/platform.h b/include/asm-arm/arch-realview/platform.h
index aef9b36b3c37..18d7c18b738c 100644
--- a/include/asm-arm/arch-realview/platform.h
+++ b/include/asm-arm/arch-realview/platform.h
@@ -209,6 +209,8 @@
#else
#define REALVIEW_MPCORE_SCU_BASE 0x10100000 /* SCU registers */
#define REALVIEW_GIC_CPU_BASE 0x10100100 /* Generic interrupt controller CPU interface */
+#define REALVIEW_TWD_BASE 0x10100700
+#define REALVIEW_TWD_SIZE 0x00000100
#define REALVIEW_GIC_DIST_BASE 0x10101000 /* Generic interrupt controller distributor */
#endif
#define REALVIEW_SMC_BASE 0x10080000 /* SMC */
@@ -305,9 +307,6 @@
#define INT_TSPENINT 30 /* Touchscreen pen */
#define INT_TSKPADINT 31 /* Touchscreen keypad */
#else
-#define INT_LOCALTIMER 29
-#define INT_LOCALWDOG 30
-
#define INT_AACI 0
#define INT_TIMERINT0_1 1
#define INT_TIMERINT2_3 2
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 19:50:09 +0000