[PATCH v2] arm/imx6: add restart support for imx6q
Shawn Guo
shawn.guo at linaro.org
Mon Dec 5 01:32:14 EST 2011
The restart support was missed from the initial imx6q submission.
The mxc_restart() does not work for imx6q. Instead, this patch adds
the restart for imx6q.
Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
Changes since v1:
* Fall into soft_restart in case that iomap for wdog_base fails
arch/arm/mach-imx/clock-imx6q.c | 2 -
arch/arm/mach-imx/mach-imx6q.c | 35 ++++++++++++++++++++++++++++++-
arch/arm/mach-imx/src.c | 23 ++++++++++++++++++++
arch/arm/plat-mxc/include/mach/common.h | 1 +
4 files changed, 58 insertions(+), 3 deletions(-)
diff --git a/arch/arm/mach-imx/clock-imx6q.c b/arch/arm/mach-imx/clock-imx6q.c
index 613a1b9..2234031 100644
--- a/arch/arm/mach-imx/clock-imx6q.c
+++ b/arch/arm/mach-imx/clock-imx6q.c
@@ -1931,14 +1931,12 @@ int imx6q_set_lpm(enum mxc_cpu_pwr_mode mode)
val |= 0x1 << BP_CLPCR_LPM;
val &= ~BM_CLPCR_VSTBY;
val &= ~BM_CLPCR_SBYOS;
- val |= BM_CLPCR_BYP_MMDC_CH1_LPM_HS;
break;
case STOP_POWER_OFF:
val |= 0x2 << BP_CLPCR_LPM;
val |= 0x3 << BP_CLPCR_STBY_COUNT;
val |= BM_CLPCR_VSTBY;
val |= BM_CLPCR_SBYOS;
- val |= BM_CLPCR_BYP_MMDC_CH1_LPM_HS;
break;
default:
return -EINVAL;
diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c
index dc8b6e2..b8236f3 100644
--- a/arch/arm/mach-imx/mach-imx6q.c
+++ b/arch/arm/mach-imx/mach-imx6q.c
@@ -10,10 +10,13 @@
* http://www.gnu.org/copyleft/gpl.html
*/
+#include <linux/delay.h>
#include <linux/init.h>
+#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <asm/hardware/cache-l2x0.h>
@@ -23,6 +26,36 @@
#include <mach/common.h>
#include <mach/hardware.h>
+void imx6q_restart(char mode, const char *cmd)
+{
+ struct device_node *np;
+ void __iomem *wdog_base;
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-wdt");
+ wdog_base = of_iomap(np, 0);
+ if (!wdog_base)
+ goto soft;
+
+ imx_src_prepare_restart();
+
+ /* enable wdog */
+ writew_relaxed(1 << 2, wdog_base);
+ /* write twice to ensure the request will not get ignored */
+ writew_relaxed(1 << 2, wdog_base);
+
+ /* wait for reset to assert ... */
+ mdelay(500);
+
+ pr_err("Watchdog reset failed to assert reset\n");
+
+ /* delay to allow the serial port to show the message */
+ mdelay(50);
+
+soft:
+ /* we'll take a jump through zero as a poor second */
+ soft_restart(0);
+}
+
static void __init imx6q_init_machine(void)
{
of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
@@ -81,5 +114,5 @@ DT_MACHINE_START(IMX6Q, "Freescale i.MX6 Quad (Device Tree)")
.timer = &imx6q_timer,
.init_machine = imx6q_init_machine,
.dt_compat = imx6q_dt_compat,
- .restart = mxc_restart,
+ .restart = imx6q_restart,
MACHINE_END
diff --git a/arch/arm/mach-imx/src.c b/arch/arm/mach-imx/src.c
index 36cacbd..117538c 100644
--- a/arch/arm/mach-imx/src.c
+++ b/arch/arm/mach-imx/src.c
@@ -18,6 +18,7 @@
#define SRC_SCR 0x000
#define SRC_GPR1 0x020
+#define BP_SRC_SCR_WARM_RESET_ENABLE 0
#define BP_SRC_SCR_CORE1_RST 14
#define BP_SRC_SCR_CORE1_ENABLE 22
@@ -39,11 +40,33 @@ void imx_set_cpu_jump(int cpu, void *jump_addr)
src_base + SRC_GPR1 + cpu * 8);
}
+void imx_src_prepare_restart(void)
+{
+ u32 val;
+
+ /* clear enable bits of secondary cores */
+ val = readl_relaxed(src_base + SRC_SCR);
+ val &= ~(0x7 << BP_SRC_SCR_CORE1_ENABLE);
+ writel_relaxed(val, src_base + SRC_SCR);
+
+ /* clear persistent entry register of primary core */
+ writel_relaxed(0, src_base + SRC_GPR1);
+}
+
void __init imx_src_init(void)
{
struct device_node *np;
+ u32 val;
np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-src");
src_base = of_iomap(np, 0);
WARN_ON(!src_base);
+
+ /*
+ * force warm reset sources to generate cold reset
+ * for a more reliable restart
+ */
+ val = readl_relaxed(src_base + SRC_SCR);
+ val &= ~(1 << BP_SRC_SCR_WARM_RESET_ENABLE);
+ writel_relaxed(val, src_base + SRC_SCR);
}
diff --git a/arch/arm/plat-mxc/include/mach/common.h b/arch/arm/plat-mxc/include/mach/common.h
index 4ee98d5..5ad0497 100644
--- a/arch/arm/plat-mxc/include/mach/common.h
+++ b/arch/arm/plat-mxc/include/mach/common.h
@@ -123,6 +123,7 @@ static inline void imx_smp_prepare(void) {}
extern void imx_enable_cpu(int cpu, bool enable);
extern void imx_set_cpu_jump(int cpu, void *jump_addr);
extern void imx_src_init(void);
+extern void imx_src_prepare_restart(void);
extern void imx_gpc_init(void);
extern void imx_gpc_pre_suspend(void);
extern void imx_gpc_post_resume(void);
--
1.7.4.1
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