[PATCH 05/13] ARM: shmobile: r8a7791: Wait for status on all MSTP clocks

Simon Horman horms+renesas at verge.net.au
Thu Feb 6 01:21:02 EST 2014


From: Shinya Kuribayashi <shinya.kuribayashi.px at renesas.com>

When enabling a module clock by clearing its bit in the MSTP control
register, the CPG requires waiting for the status register to signal
that the clock has started. Failure to do so will result in returning
from the clk_enable() call with the clock potentially still disabled,
leading to various race conditions and difficult to debug errors.

Enable status wait for all MSTP clocks on the r8a7791.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
Acked-by: Magnus Damm <damm at opensource.se>
Signed-off-by: Simon Horman <horms+renesas at verge.net.au>
---
 arch/arm/mach-shmobile/clock-r8a7791.c | 68 +++++++++++++++++++---------------
 1 file changed, 38 insertions(+), 30 deletions(-)

diff --git a/arch/arm/mach-shmobile/clock-r8a7791.c b/arch/arm/mach-shmobile/clock-r8a7791.c
index 191ad60..1074ba4 100644
--- a/arch/arm/mach-shmobile/clock-r8a7791.c
+++ b/arch/arm/mach-shmobile/clock-r8a7791.c
@@ -59,6 +59,14 @@
 #define SMSTPCR10	0xE6150998
 #define SMSTPCR11	0xE615099C
 
+#define MSTPSR1		IOMEM(0xe6150038)
+#define MSTPSR2		IOMEM(0xe6150040)
+#define MSTPSR5		IOMEM(0xe615003c)
+#define MSTPSR7		IOMEM(0xe61501c4)
+#define MSTPSR8		IOMEM(0xe61509a0)
+#define MSTPSR9		IOMEM(0xe61509a4)
+#define MSTPSR11	IOMEM(0xe61509ac)
+
 #define MODEMR		0xE6160060
 #define SDCKCR		0xE6150074
 #define SD2CKCR		0xE6150078
@@ -137,36 +145,36 @@ enum {
 };
 
 static struct clk mstp_clks[MSTP_NR] = {
-	[MSTP931] = SH_CLK_MSTP32(&p_clk, SMSTPCR9, 31, 0), /* I2C0 */
-	[MSTP930] = SH_CLK_MSTP32(&p_clk, SMSTPCR9, 30, 0), /* I2C1 */
-	[MSTP929] = SH_CLK_MSTP32(&p_clk, SMSTPCR9, 29, 0), /* I2C2 */
-	[MSTP928] = SH_CLK_MSTP32(&p_clk, SMSTPCR9, 28, 0), /* I2C3 */
-	[MSTP927] = SH_CLK_MSTP32(&p_clk, SMSTPCR9, 27, 0), /* I2C4 */
-	[MSTP925] = SH_CLK_MSTP32(&p_clk, SMSTPCR9, 25, 0), /* I2C5 */
-	[MSTP813] = SH_CLK_MSTP32(&p_clk, SMSTPCR8, 13, 0), /* Ether */
-	[MSTP811] = SH_CLK_MSTP32(&zg_clk, SMSTPCR8, 11, 0), /* VIN0 */
-	[MSTP810] = SH_CLK_MSTP32(&zg_clk, SMSTPCR8, 10, 0), /* VIN1 */
-	[MSTP809] = SH_CLK_MSTP32(&zg_clk, SMSTPCR8,  9, 0), /* VIN2 */
-	[MSTP726] = SH_CLK_MSTP32(&zx_clk, SMSTPCR7, 26, 0), /* LVDS0 */
-	[MSTP724] = SH_CLK_MSTP32(&zx_clk, SMSTPCR7, 24, 0), /* DU0 */
-	[MSTP723] = SH_CLK_MSTP32(&zx_clk, SMSTPCR7, 23, 0), /* DU1 */
-	[MSTP721] = SH_CLK_MSTP32(&p_clk, SMSTPCR7, 21, 0), /* SCIF0 */
-	[MSTP720] = SH_CLK_MSTP32(&p_clk, SMSTPCR7, 20, 0), /* SCIF1 */
-	[MSTP719] = SH_CLK_MSTP32(&p_clk, SMSTPCR7, 19, 0), /* SCIF2 */
-	[MSTP718] = SH_CLK_MSTP32(&p_clk, SMSTPCR7, 18, 0), /* SCIF3 */
-	[MSTP715] = SH_CLK_MSTP32(&p_clk, SMSTPCR7, 15, 0), /* SCIF4 */
-	[MSTP714] = SH_CLK_MSTP32(&p_clk, SMSTPCR7, 14, 0), /* SCIF5 */
-	[MSTP522] = SH_CLK_MSTP32(&extal_clk, SMSTPCR5, 22, 0), /* Thermal */
-	[MSTP216] = SH_CLK_MSTP32(&mp_clk, SMSTPCR2, 16, 0), /* SCIFB2 */
-	[MSTP207] = SH_CLK_MSTP32(&mp_clk, SMSTPCR2, 7, 0), /* SCIFB1 */
-	[MSTP206] = SH_CLK_MSTP32(&mp_clk, SMSTPCR2, 6, 0), /* SCIFB0 */
-	[MSTP204] = SH_CLK_MSTP32(&mp_clk, SMSTPCR2, 4, 0), /* SCIFA0 */
-	[MSTP203] = SH_CLK_MSTP32(&mp_clk, SMSTPCR2, 3, 0), /* SCIFA1 */
-	[MSTP202] = SH_CLK_MSTP32(&mp_clk, SMSTPCR2, 2, 0), /* SCIFA2 */
-	[MSTP1105] = SH_CLK_MSTP32(&mp_clk, SMSTPCR11, 5, 0), /* SCIFA3 */
-	[MSTP1106] = SH_CLK_MSTP32(&mp_clk, SMSTPCR11, 6, 0), /* SCIFA4 */
-	[MSTP1107] = SH_CLK_MSTP32(&mp_clk, SMSTPCR11, 7, 0), /* SCIFA5 */
-	[MSTP124] = SH_CLK_MSTP32(&rclk_clk, SMSTPCR1, 24, 0), /* CMT0 */
+	[MSTP931] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR9, 31, MSTPSR9, 0), /* I2C0 */
+	[MSTP930] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR9, 30, MSTPSR9, 0), /* I2C1 */
+	[MSTP929] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR9, 29, MSTPSR9, 0), /* I2C2 */
+	[MSTP928] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR9, 28, MSTPSR9, 0), /* I2C3 */
+	[MSTP927] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR9, 27, MSTPSR9, 0), /* I2C4 */
+	[MSTP925] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR9, 25, MSTPSR9, 0), /* I2C5 */
+	[MSTP813] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR8, 13, MSTPSR8, 0), /* Ether */
+	[MSTP811] = SH_CLK_MSTP32_STS(&zg_clk, SMSTPCR8, 11, MSTPSR8, 0), /* VIN0 */
+	[MSTP810] = SH_CLK_MSTP32_STS(&zg_clk, SMSTPCR8, 10, MSTPSR8, 0), /* VIN1 */
+	[MSTP809] = SH_CLK_MSTP32_STS(&zg_clk, SMSTPCR8, 9, MSTPSR8, 0), /* VIN2 */
+	[MSTP726] = SH_CLK_MSTP32_STS(&zx_clk, SMSTPCR7, 26, MSTPSR7, 0), /* LVDS0 */
+	[MSTP724] = SH_CLK_MSTP32_STS(&zx_clk, SMSTPCR7, 24, MSTPSR7, 0), /* DU0 */
+	[MSTP723] = SH_CLK_MSTP32_STS(&zx_clk, SMSTPCR7, 23, MSTPSR7, 0), /* DU1 */
+	[MSTP721] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR7, 21, MSTPSR7, 0), /* SCIF0 */
+	[MSTP720] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR7, 20, MSTPSR7, 0), /* SCIF1 */
+	[MSTP719] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR7, 19, MSTPSR7, 0), /* SCIF2 */
+	[MSTP718] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR7, 18, MSTPSR7, 0), /* SCIF3 */
+	[MSTP715] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR7, 15, MSTPSR7, 0), /* SCIF4 */
+	[MSTP714] = SH_CLK_MSTP32_STS(&p_clk, SMSTPCR7, 14, MSTPSR7, 0), /* SCIF5 */
+	[MSTP522] = SH_CLK_MSTP32_STS(&extal_clk, SMSTPCR5, 22, MSTPSR5, 0), /* Thermal */
+	[MSTP216] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR2, 16, MSTPSR2, 0), /* SCIFB2 */
+	[MSTP207] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR2, 7, MSTPSR2, 0), /* SCIFB1 */
+	[MSTP206] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR2, 6, MSTPSR2, 0), /* SCIFB0 */
+	[MSTP204] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR2, 4, MSTPSR2, 0), /* SCIFA0 */
+	[MSTP203] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR2, 3, MSTPSR2, 0), /* SCIFA1 */
+	[MSTP202] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR2, 2, MSTPSR2, 0), /* SCIFA2 */
+	[MSTP1105] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR11, 5, MSTPSR11, 0), /* SCIFA3 */
+	[MSTP1106] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR11, 6, MSTPSR11, 0), /* SCIFA4 */
+	[MSTP1107] = SH_CLK_MSTP32_STS(&mp_clk, SMSTPCR11, 7, MSTPSR11, 0), /* SCIFA5 */
+	[MSTP124] = SH_CLK_MSTP32_STS(&rclk_clk, SMSTPCR1, 24, MSTPSR1, 0), /* CMT0 */
 };
 
 static struct clk_lookup lookups[] = {
-- 
1.8.5.2




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