usb: cdns3: Set the USB_125M clock explicitly

Since the USB_125M clock is divided from pll0 clock,
and the pll0 clock changes per the cpu frequency.
So, needs to set the clock explicitly.

Signed-off-by: mason.huo <mason.huo@starfivetech.com>

diff --git a/drivers/usb/cdns3/cdns3-starfive.c b/drivers/usb/cdns3/cdns3-starfive.c
index a2cfefe..7adadc5 100644 (file)
--- a/drivers/usb/cdns3/cdns3-starfive.c
+++ b/drivers/usb/cdns3/cdns3-starfive.c
@@ -53,6 +53,8 @@
 #define PCIE_USB3_PHY_ENABLE_SHIFT     0x4U
 #define PCIE_USB3_PHY_ENABLE_MASK      0x10U
 
+#define USB_125M_CLK_RATE              125000000
+
 struct cdns_starfive {
        struct device *dev;
        struct regmap *stg_syscon;
@@ -60,6 +62,7 @@ struct cdns_starfive {
        struct reset_control *resets;
        struct clk_bulk_data *clks;
        int num_clks;
+       struct clk *usb_125m_clk;
        u32 sys_offset;
        u32 stg_offset_4;
        u32 stg_offset_196;
@@ -142,12 +145,29 @@ static int cdns_clk_rst_init(struct cdns_starfive *data)
 {
        int ret;
 
+       data->usb_125m_clk = devm_clk_get(data->dev, "125m");
+       if (IS_ERR(data->usb_125m_clk)) {
+               dev_err(data->dev, "Failed to get usb 125m clock\n");
+               ret = PTR_ERR(data->usb_125m_clk);
+               goto exit;
+       }
+
        data->num_clks = devm_clk_bulk_get_all(data->dev, &data->clks);
        if (data->num_clks < 0) {
                dev_err(data->dev, "Failed to get usb clocks\n");
                ret = -ENODEV;
                goto exit;
        }
+
+       /* Needs to set the USB_125M clock explicitly,
+        * since it's divided from pll0 clock, and the pll0 clock
+        * changes per the cpu frequency.
+        */
+       ret = clk_set_rate(data->usb_125m_clk, USB_125M_CLK_RATE);
+       if (ret) {
+               dev_err(data->dev, "Failed to set usb 125m clock\n");
+               goto exit;
+       }
        ret = clk_bulk_prepare_enable(data->num_clks, data->clks);
        if (ret) {
                dev_err(data->dev, "Failed to enable clocks\n");