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-rw-r--r--arch/sh/kernel/cpu/sh2/Makefile4
-rw-r--r--arch/sh/kernel/cpu/sh2/entry.S55
-rw-r--r--arch/sh/kernel/cpu/sh2/probe.c39
-rw-r--r--arch/sh/kernel/cpu/sh2/smp-j2.c139
4 files changed, 236 insertions, 1 deletions
diff --git a/arch/sh/kernel/cpu/sh2/Makefile b/arch/sh/kernel/cpu/sh2/Makefile
index f0f059acf..904c4283d 100644
--- a/arch/sh/kernel/cpu/sh2/Makefile
+++ b/arch/sh/kernel/cpu/sh2/Makefile
@@ -5,3 +5,7 @@
obj-y := ex.o probe.o entry.o
obj-$(CONFIG_CPU_SUBTYPE_SH7619) += setup-sh7619.o clock-sh7619.o
+
+# SMP setup
+smp-$(CONFIG_CPU_J2) := smp-j2.o
+obj-$(CONFIG_SMP) += $(smp-y)
diff --git a/arch/sh/kernel/cpu/sh2/entry.S b/arch/sh/kernel/cpu/sh2/entry.S
index a1505956e..1ee0a6e77 100644
--- a/arch/sh/kernel/cpu/sh2/entry.S
+++ b/arch/sh/kernel/cpu/sh2/entry.S
@@ -47,6 +47,13 @@ ENTRY(exception_handler)
mov.l r3,@-sp
cli
mov.l $cpu_mode,r2
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r3
+ mov.l @r3,r3
+ mov.l @r3,r3
+ shll2 r3
+ add r3,r2
+#endif
mov.l @r2,r0
mov.l @(5*4,r15),r3 ! previous SR
or r0,r3 ! set MD
@@ -57,6 +64,13 @@ ENTRY(exception_handler)
mov.l __md_bit,r0
mov.l r0,@r2 ! enter kernel mode
mov.l $current_thread_info,r2
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r0
+ mov.l @r0,r0
+ mov.l @r0,r0
+ shll2 r0
+ add r0,r2
+#endif
mov.l @r2,r2
mov #(THREAD_SIZE >> 8),r0
shll8 r0
@@ -147,6 +161,11 @@ ENTRY(exception_handler)
mov #31,r8
cmp/hs r8,r9
bt trap_entry ! 64 > vec >= 31 is trap
+#ifdef CONFIG_CPU_J2
+ mov #16,r8
+ cmp/hs r8,r9
+ bt interrupt_entry ! 31 > vec >= 16 is interrupt
+#endif
mov.l 4f,r8
mov r9,r4
@@ -260,6 +279,13 @@ restore_all:
lds.l @r0+,macl
mov r15,r0
mov.l $cpu_mode,r2
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r3
+ mov.l @r3,r3
+ mov.l @r3,r3
+ shll2 r3
+ add r3,r2
+#endif
mov #OFF_SR,r3
mov.l @(r0,r3),r1
mov.l __md_bit,r3
@@ -276,6 +302,13 @@ restore_all:
mov.l r1,@r2 ! set pc
get_current_thread_info r0, r1
mov.l $current_thread_info,r1
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r3
+ mov.l @r3,r3
+ mov.l @r3,r3
+ shll2 r3
+ add r3,r1
+#endif
mov.l r0,@r1
mov.l @r15+,r0
mov.l @r15+,r1
@@ -303,19 +336,41 @@ $current_thread_info:
.long __current_thread_info
$cpu_mode:
.long __cpu_mode
+#ifdef CONFIG_SMP
+$cpuid:
+ .long sh2_cpuid_addr
+#endif
! common exception handler
#include "../../entry-common.S"
+
+#ifdef CONFIG_NR_CPUS
+#define NR_CPUS CONFIG_NR_CPUS
+#else
+#define NR_CPUS 1
+#endif
.data
! cpu operation mode
! bit30 = MD (compatible SH3/4)
__cpu_mode:
+ .rept NR_CPUS
.long 0x40000000
+ .endr
+
+#ifdef CONFIG_SMP
+.global sh2_cpuid_addr
+sh2_cpuid_addr:
+ .long dummy_cpuid
+dummy_cpuid:
+ .long 0
+#endif
.section .bss
__current_thread_info:
+ .rept NR_CPUS
.long 0
+ .endr
ENTRY(exception_handling_table)
.space 4*32
diff --git a/arch/sh/kernel/cpu/sh2/probe.c b/arch/sh/kernel/cpu/sh2/probe.c
index 6c687ae81..4205f6d42 100644
--- a/arch/sh/kernel/cpu/sh2/probe.c
+++ b/arch/sh/kernel/cpu/sh2/probe.c
@@ -10,10 +10,27 @@
* for more details.
*/
#include <linux/init.h>
+#include <linux/of_fdt.h>
+#include <linux/smp.h>
+#include <linux/io.h>
#include <asm/processor.h>
#include <asm/cache.h>
-void cpu_probe(void)
+#if defined(CONFIG_CPU_J2)
+extern u32 __iomem *j2_ccr_base;
+static int __init scan_cache(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ if (!of_flat_dt_is_compatible(node, "jcore,cache"))
+ return 0;
+
+ j2_ccr_base = (u32 __iomem *)of_flat_dt_translate_address(node);
+
+ return 1;
+}
+#endif
+
+void __ref cpu_probe(void)
{
#if defined(CONFIG_CPU_SUBTYPE_SH7619)
boot_cpu_data.type = CPU_SH7619;
@@ -24,10 +41,30 @@ void cpu_probe(void)
boot_cpu_data.dcache.linesz = L1_CACHE_BYTES;
boot_cpu_data.dcache.flags = 0;
#endif
+
+#if defined(CONFIG_CPU_J2)
+ unsigned cpu = hard_smp_processor_id();
+ if (cpu == 0) of_scan_flat_dt(scan_cache, NULL);
+ if (j2_ccr_base) __raw_writel(0x80000303, j2_ccr_base + 4*cpu);
+ if (cpu != 0) return;
+ boot_cpu_data.type = CPU_J2;
+
+ /* These defaults are appropriate for the original/current
+ * J2 cache. Once there is a proper framework for getting cache
+ * info from device tree, we should switch to that. */
+ boot_cpu_data.dcache.ways = 1;
+ boot_cpu_data.dcache.sets = 256;
+ boot_cpu_data.dcache.entry_shift = 5;
+ boot_cpu_data.dcache.linesz = 32;
+ boot_cpu_data.dcache.flags = 0;
+
+ boot_cpu_data.flags |= CPU_HAS_CAS_L;
+#else
/*
* SH-2 doesn't have separate caches
*/
boot_cpu_data.dcache.flags |= SH_CACHE_COMBINED;
+#endif
boot_cpu_data.icache = boot_cpu_data.dcache;
boot_cpu_data.family = CPU_FAMILY_SH2;
}
diff --git a/arch/sh/kernel/cpu/sh2/smp-j2.c b/arch/sh/kernel/cpu/sh2/smp-j2.c
new file mode 100644
index 000000000..6ccd7e4dc
--- /dev/null
+++ b/arch/sh/kernel/cpu/sh2/smp-j2.c
@@ -0,0 +1,139 @@
+/*
+ * SMP support for J2 processor
+ *
+ * Copyright (C) 2015-2016 Smart Energy Instruments, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <asm/cmpxchg.h>
+
+DEFINE_PER_CPU(unsigned, j2_ipi_messages);
+
+extern u32 *sh2_cpuid_addr;
+static u32 *j2_ipi_trigger;
+static int j2_ipi_irq;
+
+static irqreturn_t j2_ipi_interrupt_handler(int irq, void *arg)
+{
+ unsigned cpu = hard_smp_processor_id();
+ volatile unsigned *pmsg = &per_cpu(j2_ipi_messages, cpu);
+ unsigned messages, i;
+
+ do messages = *pmsg;
+ while (cmpxchg(pmsg, messages, 0) != messages);
+
+ if (!messages) return IRQ_NONE;
+
+ for (i=0; i<SMP_MSG_NR; i++)
+ if (messages & (1U<<i))
+ smp_message_recv(i);
+
+ return IRQ_HANDLED;
+}
+
+static void j2_smp_setup(void)
+{
+}
+
+static void j2_prepare_cpus(unsigned int max_cpus)
+{
+ struct device_node *np;
+ unsigned i, max = 1;
+
+ np = of_find_compatible_node(NULL, NULL, "jcore,ipi-controller");
+ if (!np)
+ goto out;
+
+ j2_ipi_irq = irq_of_parse_and_map(np, 0);
+ j2_ipi_trigger = of_iomap(np, 0);
+ if (!j2_ipi_irq || !j2_ipi_trigger)
+ goto out;
+
+ np = of_find_compatible_node(NULL, NULL, "jcore,cpuid-mmio");
+ if (!np)
+ goto out;
+
+ sh2_cpuid_addr = of_iomap(np, 0);
+ if (!sh2_cpuid_addr)
+ goto out;
+
+ if (request_irq(j2_ipi_irq, j2_ipi_interrupt_handler, IRQF_PERCPU,
+ "ipi", (void *)j2_ipi_interrupt_handler) != 0)
+ goto out;
+
+ max = max_cpus;
+out:
+ /* Disable any cpus past max_cpus, or all secondaries if we didn't
+ * get the necessary resources to support SMP. */
+ for (i=max; i<NR_CPUS; i++) {
+ set_cpu_possible(i, false);
+ set_cpu_present(i, false);
+ }
+}
+
+static void j2_start_cpu(unsigned int cpu, unsigned long entry_point)
+{
+ struct device_node *np;
+ u32 regs[2];
+ void __iomem *release, *initpc;
+
+ if (!cpu) return;
+
+ np = of_get_cpu_node(cpu, NULL);
+ if (!np) return;
+
+ if (of_property_read_u32_array(np, "cpu-release-addr", regs, 2)) return;
+ release = ioremap_nocache(regs[0], sizeof(u32));
+ initpc = ioremap_nocache(regs[1], sizeof(u32));
+
+ __raw_writel(entry_point, initpc);
+ __raw_writel(1, release);
+
+ iounmap(initpc);
+ iounmap(release);
+
+ pr_info("J2 SMP: requested start of cpu %u\n", cpu);
+}
+
+static unsigned int j2_smp_processor_id(void)
+{
+ return __raw_readl(sh2_cpuid_addr);
+}
+
+static void j2_send_ipi(unsigned int cpu, unsigned int message)
+{
+ volatile unsigned *pmsg;
+ unsigned old;
+ unsigned long val;
+
+ /* There is only one IPI interrupt shared by all messages, so
+ * we keep a separate interrupt flag per message type in sw. */
+ pmsg = &per_cpu(j2_ipi_messages, cpu);
+ do old = *pmsg;
+ while (cmpxchg(pmsg, old, old|(1U<<message)) != old);
+
+ /* Generate the actual interrupt by writing to CCRn bit 28. */
+ val = __raw_readl(j2_ipi_trigger + cpu);
+ __raw_writel(val | (1U<<28), j2_ipi_trigger + cpu);
+}
+
+static struct plat_smp_ops j2_smp_ops = {
+ .smp_setup = j2_smp_setup,
+ .prepare_cpus = j2_prepare_cpus,
+ .start_cpu = j2_start_cpu,
+ .smp_processor_id = j2_smp_processor_id,
+ .send_ipi = j2_send_ipi,
+ .cpu_die = native_cpu_die,
+ .cpu_disable = native_cpu_disable,
+ .play_dead = native_play_dead,
+};
+
+CPU_METHOD_OF_DECLARE(j2_cpu_method, "jcore,spin-table", &j2_smp_ops);