[PATCH v10 02/11] drm/etnaviv: Add a dedicated function to get various clocks

[Sui Jingfeng]

Because it is also platform-dependent, there are systems where we don't
have DT-based clock drivers supported. For example, discrete PCI GPUs.
Therefire, don't quit if there is no clock subsystem support.
    
For the GPU in LS7A1000 and LS2K1000, the working frequency of the GPU is
rely on the GFX PLL to generate the clock. Typically, the GFX PLL is
configured by the platform firmware.

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 a03e81337d8f..5e88fa95dac2 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;
@@ -1863,27 +1892,9 @@ 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