[ARM SMP] Add Realview MPcore SMP support

Add SMP support for the MPcore tile fitted to the Realview ARM
platform.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 46 insertions, 0 deletions

diff --git a/include/asm-arm/arch-realview/entry-macro.S b/include/asm-arm/arch-realview/entry-macro.S
index 2712ba77bb3a..4df469bf42e2 100644
--- a/include/asm-arm/arch-realview/entry-macro.S
+++ b/include/asm-arm/arch-realview/entry-macro.S
@@ -47,3 +47,17 @@
                 cmpcs   \irqnr, \irqnr
 
                 .endm
+
+                /* We assume that irqstat (the raw value of the IRQ acknowledge
+                 * register) is preserved from the macro above.
+                 * If there is an IPI, we immediately signal end of interrupt on the
+                 * controller, since this requires the original irqstat value which
+                 * we won't easily be able to recreate later.
+                 */
+
+                .macro test_for_ipi, irqnr, irqstat, base, tmp
+                bic     \irqnr, \irqstat, #0x1c00
+                cmp     \irqnr, #16
+                strcc   \irqstat, [\base, #GIC_CPU_EOI]
+                cmpcs   \irqnr, \irqnr
+                .endm
diff --git a/include/asm-arm/arch-realview/platform.h b/include/asm-arm/arch-realview/platform.h
index 432260121c8b..aef9b36b3c37 100644
--- a/include/asm-arm/arch-realview/platform.h
+++ b/include/asm-arm/arch-realview/platform.h
@@ -207,6 +207,7 @@
 #define REALVIEW_GIC_CPU_BASE         0x10040000        /* Generic interrupt controller CPU interface */
 #define REALVIEW_GIC_DIST_BASE        0x10041000        /* Generic interrupt controller distributor */
 #else
+#define REALVIEW_MPCORE_SCU_BASE        0x10100000      /*  SCU registers */
 #define REALVIEW_GIC_CPU_BASE           0x10100100      /* Generic interrupt controller CPU interface */
 #define REALVIEW_GIC_DIST_BASE          0x10101000      /* Generic interrupt controller distributor */
 #endif
diff --git a/include/asm-arm/arch-realview/smp.h b/include/asm-arm/arch-realview/smp.h
new file mode 100644
index 000000000000..fc87783e8e8b
--- /dev/null
+++ b/include/asm-arm/arch-realview/smp.h
@@ -0,0 +1,31 @@
+#ifndef ASMARM_ARCH_SMP_H
+#define ASMARM_ARCH_SMP_H
+
+#include <linux/config.h>
+
+#include <asm/hardware/gic.h>
+
+#define hard_smp_processor_id()                 \
+        ({                                              \
+                unsigned int cpunum;                    \
+                __asm__("mrc p15, 0, %0, c0, c0, 5"     \
+                        : "=r" (cpunum));               \
+                cpunum &= 0x0F;                         \
+        })
+
+/*
+ * We use IRQ1 as the IPI
+ */
+static inline void smp_cross_call(cpumask_t callmap)
+{
+        gic_raise_softirq(callmap, 1);
+}
+
+/*
+ * Do nothing on MPcore.
+ */
+static inline void smp_cross_call_done(cpumask_t callmap)
+{
+}
+
+#endif