[PATCH v8 2/8] drm/etnaviv: add a dedicated function to get various clocks

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng at loongson.cn>

Because it is also platform-dependent, there are environments where don't
have CLK subsystem support, for example, discreted PCI GPUs. So don't rage
quit if there is no CLK subsystem support.

For the GPU in LS7A1000 and LS2K1000, the working frequency of the GPU is
tuned by configuring the PLL registers.

Cc: Lucas Stach <l.stach at pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner at gmail.com>
Cc: Philipp Zabel <p.zabel at pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas at google.com>
Cc: Daniel Vetter <daniel at ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng at loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 53 ++++++++++++++++-----------
 1 file changed, 32 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index b9c12d3145a2..d4f99cb0456f 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -1565,6 +1565,35 @@ static irqreturn_t irq_handler(int irq, void *data)
 	return ret;
 }
 
+static int etnaviv_gpu_clk_get(struct etnaviv_gpu *gpu)
+{
+	struct device *dev = gpu->dev;
+
+	gpu->clk_reg = devm_clk_get_optional(dev, "reg");
+	DBG("clk_reg: %p", gpu->clk_reg);
+	if (IS_ERR(gpu->clk_reg))
+		return PTR_ERR(gpu->clk_reg);
+
+	gpu->clk_bus = devm_clk_get_optional(dev, "bus");
+	DBG("clk_bus: %p", gpu->clk_bus);
+	if (IS_ERR(gpu->clk_bus))
+		return PTR_ERR(gpu->clk_bus);
+
+	gpu->clk_core = devm_clk_get(dev, "core");
+	DBG("clk_core: %p", gpu->clk_core);
+	if (IS_ERR(gpu->clk_core))
+		return PTR_ERR(gpu->clk_core);
+	gpu->base_rate_core = clk_get_rate(gpu->clk_core);
+
+	gpu->clk_shader = devm_clk_get_optional(dev, "shader");
+	DBG("clk_shader: %p", gpu->clk_shader);
+	if (IS_ERR(gpu->clk_shader))
+		return PTR_ERR(gpu->clk_shader);
+	gpu->base_rate_shader = clk_get_rate(gpu->clk_shader);
+
+	return 0;
+}
+
 static int etnaviv_gpu_clk_enable(struct etnaviv_gpu *gpu)
 {
 	int ret;
@@ -1865,27 +1894,9 @@ static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
 		return err;
 
 	/* Get Clocks: */
-	gpu->clk_reg = devm_clk_get_optional(&pdev->dev, "reg");
-	DBG("clk_reg: %p", gpu->clk_reg);
-	if (IS_ERR(gpu->clk_reg))
-		return PTR_ERR(gpu->clk_reg);
-
-	gpu->clk_bus = devm_clk_get_optional(&pdev->dev, "bus");
-	DBG("clk_bus: %p", gpu->clk_bus);
-	if (IS_ERR(gpu->clk_bus))
-		return PTR_ERR(gpu->clk_bus);
-
-	gpu->clk_core = devm_clk_get(&pdev->dev, "core");
-	DBG("clk_core: %p", gpu->clk_core);
-	if (IS_ERR(gpu->clk_core))
-		return PTR_ERR(gpu->clk_core);
-	gpu->base_rate_core = clk_get_rate(gpu->clk_core);
-
-	gpu->clk_shader = devm_clk_get_optional(&pdev->dev, "shader");
-	DBG("clk_shader: %p", gpu->clk_shader);
-	if (IS_ERR(gpu->clk_shader))
-		return PTR_ERR(gpu->clk_shader);
-	gpu->base_rate_shader = clk_get_rate(gpu->clk_shader);
+	err = etnaviv_gpu_clk_get(gpu);
+	if (err)
+		return err;
 
 	/* TODO: figure out max mapped size */
 	dev_set_drvdata(dev, gpu);
-- 
2.25.1