drm/vc4: hdmi: Rework hdmi_enable_4kp60 detection code

In order to support higher HDMI frequencies, users have to set the
hdmi_enable_4kp60 parameter in their config.txt file.

This will have the side-effect of raising the maximum of the core clock,
tied to the HVS, and managed by the HVS driver.

However, we are querying this in the HDMI driver by poking into the HVS
structure to get our struct clk handle.

Let's make this part of the HVS bind implementation to have all the core
clock related setup in the same place.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://lore.kernel.org/r/20220815-rpi-fix-4k-60-v5-5-fe9e7ac8b111@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 4ac9f5a2d5f9..fc4b7310bf63 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -28,6 +28,8 @@
 #include <drm/drm_drv.h>
 #include <drm/drm_vblank.h>
 
+#include <soc/bcm2835/raspberrypi-firmware.h>
+
 #include "vc4_drv.h"
 #include "vc4_regs.h"
 
@@ -791,12 +793,33 @@ static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
 	hvs->regset.nregs = ARRAY_SIZE(hvs_regs);
 
 	if (vc4->is_vc5) {
+		struct rpi_firmware *firmware;
+		struct device_node *node;
+		unsigned int max_rate;
+
+		node = rpi_firmware_find_node();
+		if (!node)
+			return -EINVAL;
+
+		firmware = rpi_firmware_get(node);
+		of_node_put(node);
+		if (!firmware)
+			return -EPROBE_DEFER;
+
 		hvs->core_clk = devm_clk_get(&pdev->dev, NULL);
 		if (IS_ERR(hvs->core_clk)) {
 			dev_err(&pdev->dev, "Couldn't get core clock\n");
 			return PTR_ERR(hvs->core_clk);
 		}
 
+		max_rate = rpi_firmware_clk_get_max_rate(firmware,
+							 RPI_FIRMWARE_CORE_CLK_ID);
+		rpi_firmware_put(firmware);
+		if (max_rate >= 550000000)
+			hvs->vc5_hdmi_enable_hdmi_20 = true;
+
+		hvs->max_core_rate = max_rate;
+
 		ret = clk_prepare_enable(hvs->core_clk);
 		if (ret) {
 			dev_err(&pdev->dev, "Couldn't enable the core clock\n");