soc: xilinx: vcu: register PLL as fixed rate clock

Currently, xvcu_pll_set_rate configures the PLL to a clock rate that is
pre-calculated when probing the driver. To still make the clock
framework aware of the PLL and to allow to configure other clocks based
on the PLL rate, register the PLL as a fixed rate clock.

Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/20210121071659.1226489-8-m.tretter@pengutronix.de
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: tretter

drivers/soc/xilinx/Kconfig

@@ -3,7 +3,7 @@ menu "Xilinx SoC drivers"
 
 config XILINX_VCU
 	tristate "Xilinx VCU logicoreIP Init"
-	depends on HAS_IOMEM
+	depends on HAS_IOMEM && COMMON_CLK
 	select REGMAP_MMIO
 	help
 	  Provides the driver to enable and disable the isolation between the

drivers/soc/xilinx/xlnx_vcu.c

@@ -7,6 +7,7 @@
  * Contacts   Dhaval Shah <dshah@xilinx.com>
  */
 #include <linux/clk.h>
+#include <linux/clk-provider.h>
 #include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/io.h>
@@ -73,13 +74,15 @@
  * @aclk: axi clock source
  * @logicore_reg_ba: logicore reg base address
  * @vcu_slcr_ba: vcu_slcr Register base address
+ * @pll: handle for the VCU PLL
  */
 struct xvcu_device {
 	struct device *dev;
 	struct clk *pll_ref;
 	struct clk *aclk;
 	struct regmap *logicore_reg_ba;
 	void __iomem *vcu_slcr_ba;
+	struct clk_hw *pll;
 };
 
 static struct regmap_config vcu_settings_regmap_config = {
@@ -403,7 +406,9 @@ static int xvcu_set_vcu_pll_info(struct xvcu_device *xvcu)
 	u32 clkoutdiv, vcu_pll_ctrl, pll_clk;
 	u32 mod, ctrl;
 	int i;
+	int ret;
 	const struct xvcu_pll_cfg *found = NULL;
+	struct clk_hw *hw;
 
 	regmap_read(xvcu->logicore_reg_ba, VCU_PLL_CLK, &inte);
 	regmap_read(xvcu->logicore_reg_ba, VCU_PLL_CLK_DEC, &deci);
@@ -505,7 +510,18 @@ static int xvcu_set_vcu_pll_info(struct xvcu_device *xvcu)
 	ctrl |= (VCU_SRCSEL_PLL & VCU_SRCSEL_MASK) << VCU_SRCSEL_SHIFT;
 	xvcu_write(xvcu->vcu_slcr_ba, VCU_DEC_MCU_CTRL, ctrl);
 
-	return xvcu_pll_set_rate(xvcu, fvco, refclk);
+	ret = xvcu_pll_set_rate(xvcu, fvco, refclk);
+	if (ret)
+		return ret;
+
+	hw = clk_hw_register_fixed_rate(xvcu->dev, "vcu_pll",
+					__clk_get_name(xvcu->pll_ref),
+					0, pll_clk);
+	if (IS_ERR(hw))
+		return PTR_ERR(hw);
+	xvcu->pll = hw;
+
+	return 0;
 }
 
 /**
@@ -652,6 +668,7 @@ static int xvcu_remove(struct platform_device *pdev)
 	/* Add the the Gasket isolation and put the VCU in reset. */
 	regmap_write(xvcu->logicore_reg_ba, VCU_GASKET_INIT, 0);
 
+	clk_hw_unregister_fixed_rate(xvcu->pll);
 	xvcu_pll_disable(xvcu);
 	clk_disable_unprepare(xvcu->aclk);