[U-Boot] [PATCH 1/4] ARM: atmel: use pcr to enable or disable peripheral clock

Bo Shen voice.shen at atmel.com
Wed Aug 6 11:24:54 CEST 2014


When use pcr (peripheral control register), then we won't need
to care about the peripheral ID.

Signed-off-by: Bo Shen <voice.shen at atmel.com>
---

 arch/arm/cpu/armv7/at91/clock.c           | 24 ++++++++++++++++++++----
 arch/arm/include/asm/arch-at91/at91_pmc.h |  4 ++++
 arch/arm/include/asm/arch-at91/clk.h      |  1 +
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/arch/arm/cpu/armv7/at91/clock.c b/arch/arm/cpu/armv7/at91/clock.c
index 1588e0c..36ed4a6 100644
--- a/arch/arm/cpu/armv7/at91/clock.c
+++ b/arch/arm/cpu/armv7/at91/clock.c
@@ -114,9 +114,25 @@ int at91_clock_init(unsigned long main_clock)
 void at91_periph_clk_enable(int id)
 {
 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
+	u32 regval;
 
-	if (id > 31)
-		writel(1 << (id - 32), &pmc->pcer1);
-	else
-		writel(1 << id, &pmc->pcer);
+	if (id > AT91_PMC_PCR_PID_MASK)
+		return;
+
+	regval = AT91_PMC_PCR_EN | AT91_PMC_PCR_CMD_WRITE | id;
+
+	writel(regval, &pmc->pcr);
+}
+
+void at91_periph_clk_disable(int id)
+{
+	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
+	u32 regval;
+
+	if (id > AT91_PMC_PCR_PID_MASK)
+		return;
+
+	regval = AT91_PMC_PCR_CMD_WRITE | id;
+
+	writel(regval, &pmc->pcr);
 }
diff --git a/arch/arm/include/asm/arch-at91/at91_pmc.h b/arch/arm/include/asm/arch-at91/at91_pmc.h
index 04f6239..bef5793 100644
--- a/arch/arm/include/asm/arch-at91/at91_pmc.h
+++ b/arch/arm/include/asm/arch-at91/at91_pmc.h
@@ -147,6 +147,10 @@ typedef struct at91_pmc {
 #define AT91_PMC_IXR_PCKRDY3		0x00000800
 #define AT91_PMC_IXR_MOSCSELS		0x00010000
 
+#define AT91_PMC_PCR_PID_MASK		(0x3f)
+#define AT91_PMC_PCR_CMD_WRITE		(0x1 << 12)
+#define AT91_PMC_PCR_EN			(0x1 << 28)
+
 #define		AT91_PMC_PCK		(1 <<  0)		/* Processor Clock */
 #define		AT91RM9200_PMC_UDP	(1 <<  1)		/* USB Devcice Port Clock [AT91RM9200 only] */
 #define		AT91RM9200_PMC_MCKUDP	(1 <<  2)		/* USB Device Port Master Clock Automatic Disable on Suspend [AT91RM9200 only] */
diff --git a/arch/arm/include/asm/arch-at91/clk.h b/arch/arm/include/asm/arch-at91/clk.h
index ce9e28f..4076a78 100644
--- a/arch/arm/include/asm/arch-at91/clk.h
+++ b/arch/arm/include/asm/arch-at91/clk.h
@@ -80,4 +80,5 @@ static inline unsigned long get_mci_clk_rate(void)
 
 int at91_clock_init(unsigned long main_clock);
 void at91_periph_clk_enable(int id);
+void at91_periph_clk_disable(int id);
 #endif /* __ASM_ARM_ARCH_CLK_H__ */
-- 
1.8.5.2



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