[PATCH v3 07/12] arm: zynq: Add support for system reset
Michal Simek
michal.simek at xilinx.com
Thu Mar 28 12:38:07 EDT 2013
Do system reset via slcr registers.
Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---
v3: Use zynq_ prefix for all zynq specific functions
v2: Fix comment
use writel instead of __raw_writel
Do not use PSS - use PS instead
---
arch/arm/mach-zynq/common.c | 6 ++++++
arch/arm/mach-zynq/common.h | 1 +
arch/arm/mach-zynq/slcr.c | 27 +++++++++++++++++++++++++++
3 files changed, 34 insertions(+)
diff --git a/arch/arm/mach-zynq/common.c b/arch/arm/mach-zynq/common.c
index cd3968c..f0a8533 100644
--- a/arch/arm/mach-zynq/common.c
+++ b/arch/arm/mach-zynq/common.c
@@ -92,6 +92,11 @@ static void __init xilinx_map_io(void)
zynq_scu_map_io();
}
+static void zynq_system_reset(char mode, const char *cmd)
+{
+ zynq_slcr_system_reset();
+}
+
static const char *xilinx_dt_match[] = {
"xlnx,zynq-zc702",
"xlnx,zynq-7000",
@@ -104,4 +109,5 @@ MACHINE_START(XILINX_EP107, "Xilinx Zynq Platform")
.init_machine = xilinx_init_machine,
.init_time = xilinx_zynq_timer_init,
.dt_compat = xilinx_dt_match,
+ .restart = zynq_system_reset,
MACHINE_END
diff --git a/arch/arm/mach-zynq/common.h b/arch/arm/mach-zynq/common.h
index dd594e6..d7ec3ca 100644
--- a/arch/arm/mach-zynq/common.h
+++ b/arch/arm/mach-zynq/common.h
@@ -18,6 +18,7 @@
#define __MACH_ZYNQ_COMMON_H__
extern int zynq_slcr_init(void);
+extern void zynq_slcr_system_reset(void);
extern void __iomem *zynq_slcr_base;
extern void __iomem *zynq_scu_base;
diff --git a/arch/arm/mach-zynq/slcr.c b/arch/arm/mach-zynq/slcr.c
index f9f3349..d58c996 100644
--- a/arch/arm/mach-zynq/slcr.c
+++ b/arch/arm/mach-zynq/slcr.c
@@ -32,9 +32,36 @@
#define SLCR_UNLOCK_MAGIC 0xDF0D
#define SLCR_UNLOCK 0x8 /* SCLR unlock register */
+#define SLCR_PS_RST_CTRL_OFFSET 0x200 /* PS Software Reset Control */
+#define SLCR_REBOOT_STATUS 0x258 /* PS Reboot Status */
+
void __iomem *zynq_slcr_base;
/**
+ * zynq_slcr_system_reset - Reset the entire system.
+ */
+void zynq_slcr_system_reset(void)
+{
+ u32 reboot;
+
+ /*
+ * Unlock the SLCR then reset the system.
+ * Note that this seems to require raw i/o
+ * functions or there's a lockup?
+ */
+ writel(SLCR_UNLOCK_MAGIC, zynq_slcr_base + SLCR_UNLOCK);
+
+ /*
+ * Clear 0x0F000000 bits of reboot status register to workaround
+ * the FSBL not loading the bitstream after soft-reboot
+ * This is a temporary solution until we know more.
+ */
+ reboot = readl(zynq_slcr_base + SLCR_REBOOT_STATUS);
+ writel(reboot & 0xF0FFFFFF, zynq_slcr_base + SLCR_REBOOT_STATUS);
+ writel(1, zynq_slcr_base + SLCR_PS_RST_CTRL_OFFSET);
+}
+
+/**
* zynq_slcr_init
* Returns 0 on success, negative errno otherwise.
*
--
1.7.9.7
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