[PATCH] clk/qcom: apq8016: allow apq8016_clk_init_uart() to be called externally

Caleb Connolly caleb.connolly at linaro.org
Fri Mar 1 16:00:24 CET 2024


When U-Boot as running as the first stage bootloader on MSM8916 devices,
early debug UART requires turning on the clocks (for some reason the
pre-loader turns them off?!).

To simplify developing for this platform, allow the
apq8016_clk_init_uart() function to be called externally. Developers can
call this from the serial_msm debug uart driver to configure the clocks
before the driver model is available.

As it is only possible to enable early debug UART in custom builds of
U-Boot, this solution at least gives developers the option.

Signed-off-by: Caleb Connolly <caleb.connolly at linaro.org>
---
This patch was meant to be in v5 of my Qualcomm generic board support series[1],
but got lost somewhere in the mix.

[1]: https://lore.kernel.org/u-boot/CAFA6WYNXE3x8sKRB8BBpODCfXbZeeVpKPu0-qt7ezsY-R7unQQ@mail.gmail.com/
---
 drivers/clk/qcom/clock-apq8016.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/clk/qcom/clock-apq8016.c b/drivers/clk/qcom/clock-apq8016.c
index 9de0ad5ed32d..e6647f7c41dd 100644
--- a/drivers/clk/qcom/clock-apq8016.c
+++ b/drivers/clk/qcom/clock-apq8016.c
@@ -102,22 +102,22 @@ static const struct bcr_regs uart2_regs = {
 	.D = BLSP1_UART2_APPS_D,
 };
 
 /* UART: 115200 */
-static int clk_init_uart(struct msm_clk_priv *priv)
+int apq8016_clk_init_uart(phys_addr_t base)
 {
 	/* Enable AHB clock */
-	clk_enable_vote_clk(priv->base, &gcc_blsp1_ahb_clk);
+	clk_enable_vote_clk(base, &gcc_blsp1_ahb_clk);
 
 	/* 7372800 uart block clock @ GPLL0 */
-	clk_rcg_set_rate_mnd(priv->base, &uart2_regs, 1, 144, 15625,
+	clk_rcg_set_rate_mnd(base, &uart2_regs, 1, 144, 15625,
 			     CFG_CLK_SRC_GPLL0, 16);
 
 	/* Vote for gpll0 clock */
-	clk_enable_gpll0(priv->base, &gpll0_vote_clk);
+	clk_enable_gpll0(base, &gpll0_vote_clk);
 
 	/* Enable core clk */
-	clk_enable_cbc(priv->base + BLSP1_UART2_APPS_CBCR);
+	clk_enable_cbc(base + BLSP1_UART2_APPS_CBCR);
 
 	return 0;
 }
 
@@ -132,9 +132,9 @@ static ulong apq8016_clk_set_rate(struct clk *clk, ulong rate)
 	case GCC_SDCC2_APPS_CLK: /* SDC2 */
 		return clk_init_sdc(priv, 1, rate);
 		break;
 	case GCC_BLSP1_UART2_APPS_CLK: /* UART2 */
-		return clk_init_uart(priv);
+		return apq8016_clk_init_uart(priv->base);
 		break;
 	default:
 		return 0;
 	}
-- 
2.43.1



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