[PATCH 1/3] ARM: Xilinx: add timer and on chip memory support for SMP

John Linn john.linn at xilinx.com
Sun Apr 3 17:00:16 EDT 2011


These changes are required to support SMP.

This includes an update so that the non-local timer is set
to run on the 1st CPU, the addition of local timer support
and support for on chip memory.

Signed-off-by: John Linn <john.linn at xilinx.com>
---
 arch/arm/mach-xilinx/common.c                  |   16 ++++++++++-
 arch/arm/mach-xilinx/include/mach/irqs.h       |    1 +
 arch/arm/mach-xilinx/include/mach/xilinx_soc.h |   20 +++++++++++++
 arch/arm/mach-xilinx/localtimer.c              |   36 ++++++++++++++++++++++++
 arch/arm/mach-xilinx/timer.c                   |    4 +-
 5 files changed, 74 insertions(+), 3 deletions(-)
 create mode 100644 arch/arm/mach-xilinx/localtimer.c

diff --git a/arch/arm/mach-xilinx/common.c b/arch/arm/mach-xilinx/common.c
index 83b549d..2695b39 100644
--- a/arch/arm/mach-xilinx/common.c
+++ b/arch/arm/mach-xilinx/common.c
@@ -101,7 +101,21 @@ static struct map_desc io_desc[] __initdata = {
 		.type		= MT_DEVICE,
 	},
 #endif
-
+	/* create a mapping for the OCM  (256K) leaving a hole for the
+	 * interrupt vectors which are handled in the kernel
+	 */
+	{
+		.virtual	= OCM_LOW_VIRT,
+		.pfn		= __phys_to_pfn(OCM_LOW_PHYS),
+		.length		= (192 * SZ_1K),
+		.type		= MT_DEVICE_CACHED,
+	},
+	{
+		.virtual	= OCM_HIGH_VIRT,
+		.pfn		= __phys_to_pfn(OCM_HIGH_PHYS),
+		.length		= (60 * SZ_1K),
+		.type		= MT_DEVICE,
+	},
 };
 
 /**
diff --git a/arch/arm/mach-xilinx/include/mach/irqs.h b/arch/arm/mach-xilinx/include/mach/irqs.h
index 47a8162..8c41b22 100644
--- a/arch/arm/mach-xilinx/include/mach/irqs.h
+++ b/arch/arm/mach-xilinx/include/mach/irqs.h
@@ -22,6 +22,7 @@
  * GIC Interrupts
  */
 
+#define IRQ_SCU_CPU_TIMER	29
 #define IRQ_GIC_SPI_START	32
 #define IRQ_TIMERCOUNTER0	42
 #define IRQ_UART0		59
diff --git a/arch/arm/mach-xilinx/include/mach/xilinx_soc.h b/arch/arm/mach-xilinx/include/mach/xilinx_soc.h
index d181c5c..a55a46c 100644
--- a/arch/arm/mach-xilinx/include/mach/xilinx_soc.h
+++ b/arch/arm/mach-xilinx/include/mach/xilinx_soc.h
@@ -31,13 +31,33 @@
 #define SCU_PERIPH_PHYS			0xF8F00000
 #define SCU_PERIPH_VIRT			SCU_PERIPH_PHYS
 
+#define OCM_LOW_PHYS			0xFFFC0000
+#define OCM_LOW_VIRT			OCM_LOW_PHYS
+
+#define OCM_HIGH_PHYS			0xFFFF1000
+#define OCM_HIGH_VIRT			OCM_HIGH_PHYS
+
 /* The following are intended for the devices that are mapped early */
 
 #define TTC0_BASE			IOMEM(TTC0_VIRT)
 #define SCU_PERIPH_BASE			IOMEM(SCU_PERIPH_VIRT)
 #define SCU_GIC_CPU_BASE		(SCU_PERIPH_BASE + 0x100)
+#define SCU_CPU_TIMER_BASE		(SCU_PERIPH_BASE + 0x600)
 #define SCU_GIC_DIST_BASE		(SCU_PERIPH_BASE + 0x1000)
 #define PL310_L2CC_BASE			IOMEM(PL310_L2CC_VIRT)
+#define OCM_LOW_BASE			IOMEM(OCM_LOW_VIRT)
+#define OCM_HIGH_BASE			IOMEM(OCM_HIGH_VIRT)
+
+/* There are a couple ram addresses needed for communication between the boot
+ * loader software and the linux kernel with multiple cpus in the kernel (SMP).
+ * The memory addresses are in the high on-chip RAM and these addresses are
+ * mapped flat (virtual = physical). The memory must be mapped early and
+ * non-cached.
+ */
+
+#define BOOT_ADDR_OFFSET	0xEFF0
+#define BOOT_LOCK_OFFSET	0xEFF4
+#define BOOT_LOCK_KEY		0xFACECAFE
 
 /*
  * Mandatory for CONFIG_LL_DEBUG, UART is mapped virtual = physical
diff --git a/arch/arm/mach-xilinx/localtimer.c b/arch/arm/mach-xilinx/localtimer.c
new file mode 100644
index 0000000..4bd0a0d
--- /dev/null
+++ b/arch/arm/mach-xilinx/localtimer.c
@@ -0,0 +1,36 @@
+/*
+ * arch/arm/mach-xilinx/localtimer.c
+ *
+ * Both cortex-a9 cores have their own timer in it's CPU domain.
+ *
+ * Copyright (C) 2011 Xilinx, Inc.
+ *
+ * This file is based on arch/arm/plat-versatile/localtimer.c
+ *
+ * Copyright (C) 2002 ARM Ltd.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that 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.
+ */
+#include <linux/init.h>
+#include <asm/smp_twd.h>
+#include <mach/xilinx_soc.h>
+
+/*
+ * Setup the local clock events for a CPU.
+ */
+int __cpuinit local_timer_setup(struct clock_event_device *evt)
+{
+	twd_base = SCU_CPU_TIMER_BASE;
+
+	evt->irq = IRQ_SCU_CPU_TIMER;
+	twd_timer_setup(evt);
+	return 0;
+}
+
diff --git a/arch/arm/mach-xilinx/timer.c b/arch/arm/mach-xilinx/timer.c
index b2a72f0..65c336a 100644
--- a/arch/arm/mach-xilinx/timer.c
+++ b/arch/arm/mach-xilinx/timer.c
@@ -283,9 +283,9 @@ static void __init xttcpss_timer_init(void)
 	xttcpss_clockevent.min_delta_ns =
 		clockevent_delta2ns(1, &xttcpss_clockevent);
 
-	/* Indicate that clock event can be used on any of the CPUs */
+	/* Indicate that clock event is on 1st CPU as SMP boot needs it */
 
-	xttcpss_clockevent.cpumask = cpu_all_mask;
+	xttcpss_clockevent.cpumask = cpumask_of(0);
 	clockevents_register_device(&xttcpss_clockevent);
 }
 
-- 
1.5.4.7



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