Commit a3ab984b authored by Michael Tretter's avatar Michael Tretter Committed by Stephen Boyd
Browse files

soc: xilinx: vcu: add helper to wait for PLL locked 



Extract a helper function to wait until the PLL is locked. Also,
disabling the bypass was buried in the exit path on the wait loop.
Separate the different steps and add a helper function to make the code
more readable.

Signed-off-by: default avatarMichael Tretter <m.tretter@pengutronix.de>
Acked-by: default avatarMichal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/20210121071659.1226489-5-m.tretter@pengutronix.de


Signed-off-by: default avatarStephen Boyd <sboyd@kernel.org>
parent d387dfc4

drivers/soc/xilinx/xlnx_vcu.c

+27 −19
Original line number Diff line number Diff line
@@ -256,6 +256,22 @@ static void xvcu_write_field_reg(void __iomem *iomem, int offset, 
	xvcu_write(iomem, offset, val);

}



static int xvcu_pll_wait_for_lock(struct xvcu_device *xvcu)

{

	void __iomem *base = xvcu->vcu_slcr_ba;

	unsigned long timeout;

	u32 lock_status;



	timeout = jiffies + msecs_to_jiffies(2000);

	do {

		lock_status = xvcu_read(base, VCU_PLL_STATUS);

		if (lock_status & VCU_PLL_STATUS_LOCK_STATUS_MASK)

			return 0;

	} while (!time_after(jiffies, timeout));



	return -ETIMEDOUT;

}



/**

 * xvcu_set_vcu_pll_info - Set the VCU PLL info

 * @xvcu:	Pointer to the xvcu_device structure
@@ -428,8 +444,6 @@ static int xvcu_set_vcu_pll_info(struct xvcu_device *xvcu) 
 */

static int xvcu_set_pll(struct xvcu_device *xvcu)

{

	u32 lock_status;

	unsigned long timeout;

	int ret;



	ret = xvcu_set_vcu_pll_info(xvcu);
@@ -447,24 +461,18 @@ static int xvcu_set_pll(struct xvcu_device *xvcu) 
	xvcu_write_field_reg(xvcu->vcu_slcr_ba, VCU_PLL_CTRL,

			     0, VCU_PLL_CTRL_RESET_MASK,

			     VCU_PLL_CTRL_RESET_SHIFT);

	/*

	 * Defined the timeout for the max time to wait the

	 * PLL_STATUS to be locked.

	 */

	timeout = jiffies + msecs_to_jiffies(2000);

	do {

		lock_status = xvcu_read(xvcu->vcu_slcr_ba, VCU_PLL_STATUS);

		if (lock_status & VCU_PLL_STATUS_LOCK_STATUS_MASK) {



	ret = xvcu_pll_wait_for_lock(xvcu);

	if (ret) {

		dev_err(xvcu->dev, "PLL is not locked\n");

		return ret;

	}



	xvcu_write_field_reg(xvcu->vcu_slcr_ba, VCU_PLL_CTRL,

			     0, VCU_PLL_CTRL_BYPASS_MASK,

			     VCU_PLL_CTRL_BYPASS_SHIFT);

			return 0;

		}

	} while (!time_after(jiffies, timeout));



	/* PLL is not locked even after the timeout of the 2sec */

	dev_err(xvcu->dev, "PLL is not locked\n");

	return -ETIMEDOUT;

	return ret;

}



/**