[PATCH 1/2] clk: imx: Add common API for masking MMDC handshake

From: Anson Huang
Date: Sun May 05 2019 - 02:19:38 EST


All i.MX6 SoCs need to mask unused MMDC channel's handshake
for low power modes, this patch provides common API for masking
the MMDC channel passed from caller.

Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
---
drivers/clk/imx/clk.c | 14 ++++++++++++++
drivers/clk/imx/clk.h | 1 +
2 files changed, 15 insertions(+)

diff --git a/drivers/clk/imx/clk.c b/drivers/clk/imx/clk.c
index 1efed86..6f9bcee 100644
--- a/drivers/clk/imx/clk.c
+++ b/drivers/clk/imx/clk.c
@@ -6,8 +6,22 @@
#include <linux/spinlock.h>
#include "clk.h"

+#define CCM_CCDR 0x4
+#define CCDR_MMDC_CH0_MASK BIT(17)
+#define CCDR_MMDC_CH1_MASK BIT(16)
+
DEFINE_SPINLOCK(imx_ccm_lock);

+void __init imx_mmdc_mask_handshake(void __iomem *ccm_base,
+ unsigned int chn)
+{
+ unsigned int reg;
+
+ reg = readl_relaxed(ccm_base + CCM_CCDR);
+ reg |= chn == 0 ? CCDR_MMDC_CH0_MASK : CCDR_MMDC_CH1_MASK;
+ writel_relaxed(reg, ccm_base + CCM_CCDR);
+}
+
void __init imx_check_clocks(struct clk *clks[], unsigned int count)
{
unsigned i;
diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
index 8639a8f..6dcdc91 100644
--- a/drivers/clk/imx/clk.h
+++ b/drivers/clk/imx/clk.h
@@ -10,6 +10,7 @@ extern spinlock_t imx_ccm_lock;
void imx_check_clocks(struct clk *clks[], unsigned int count);
void imx_check_clk_hws(struct clk_hw *clks[], unsigned int count);
void imx_register_uart_clocks(struct clk ** const clks[]);
+void imx_mmdc_mask_handshake(void __iomem *ccm_base, unsigned int chn);

extern void imx_cscmr1_fixup(u32 *val);

--
2.7.4