From mboxrd@z Thu Jan 1 00:00:00 1970
From: p.zabel@pengutronix.de (Philipp Zabel)
Date: Mon, 11 Jul 2016 13:11:59 +0200
Subject: [PATCH v5 1/3] clk: imx6: Mask mmdc_ch1 handshake for periph2_sel and
mmdc_ch1_axi_podf
Message-ID: <1468235521-3163-1-git-send-email-p.zabel@pengutronix.de>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org
MMDC CH1 is not used on i.MX6Q, so the handshake needed to change the
parent of periph2_sel or the divider of mmdc_ch1_axi_podf will never
succeed.
Disable the handshake mechanism to allow changing the frequency of
mmdc_ch1_axi, allowing to use it as a possible source for the LDB DI
clock.
Signed-off-by: Philipp Zabel
---
drivers/clk/imx/clk-imx6q.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/drivers/clk/imx/clk-imx6q.c b/drivers/clk/imx/clk-imx6q.c
index ba1c1ae..dd33ebc 100644
--- a/drivers/clk/imx/clk-imx6q.c
+++ b/drivers/clk/imx/clk-imx6q.c
@@ -156,6 +156,19 @@ static struct clk ** const uart_clks[] __initconst = {
NULL
};
+#define CCM_CCDR 0x04
+
+#define CCDR_MMDC_CH1_MASK BIT(16)
+
+static void __init imx6q_mmdc_ch1_mask_handshake(void __iomem *ccm_base)
+{
+ unsigned int reg;
+
+ reg = readl_relaxed(ccm_base + CCM_CCDR);
+ reg |= CCDR_MMDC_CH1_MASK;
+ writel_relaxed(reg, ccm_base + CCM_CCDR);
+}
+
static void __init imx6q_clocks_init(struct device_node *ccm_node)
{
struct device_node *np;
@@ -297,6 +310,8 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node)
base = of_iomap(np, 0);
WARN_ON(!base);
+ imx6q_mmdc_ch1_mask_handshake(base);
+
/* name reg shift width parent_names num_parents */
clk[IMX6QDL_CLK_STEP] = imx_clk_mux("step", base + 0xc, 8, 1, step_sels, ARRAY_SIZE(step_sels));
clk[IMX6QDL_CLK_PLL1_SW] = imx_clk_mux("pll1_sw", base + 0xc, 2, 1, pll1_sw_sels, ARRAY_SIZE(pll1_sw_sels));
--
2.8.1