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 <[email protected]> Reviewed-by: Dong Aisheng <[email protected]> --- Changes since V1: - add necessary "io.h" head file to avoid build error based on latest linux-next. --- drivers/clk/imx/clk.c | 15 +++++++++++++++ drivers/clk/imx/clk.h | 1 + 2 files changed, 16 insertions(+) diff --git a/drivers/clk/imx/clk.c b/drivers/clk/imx/clk.c index 1efed86..9cd7097 100644 --- a/drivers/clk/imx/clk.c +++ b/drivers/clk/imx/clk.c @@ -1,13 +1,28 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/clk.h> #include <linux/err.h> +#include <linux/io.h> #include <linux/of.h> #include <linux/slab.h> #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
