Hi,
The VC4 driver has had limited support to disable the HDMI controllers and pixelvalves at boot if the firmware has enabled them.
However, this proved to be limited, and a bit unreliable so a new firmware command has been introduced some time ago to make it free all its resources and disable any display output it might have enabled.
This series takes advantage of that command to call it once the transition from simplefb to the KMS driver has been done.
Let me know what you think, Maxime
---
Changes from v2: - Switch back to rpi_firmware_get / rpi_firmware_put - Moved the rpi_firmware pointer to a local variable
Changes from v1: - Use of_find_compatible_node instead of a phandle - Use devm_rpi_firmware_get
Maxime Ripard (3): firmware: raspberrypi: Add RPI_FIRMWARE_NOTIFY_DISPLAY_DONE drm/vc4: Remove conflicting framebuffers before callind bind_all drm/vc4: Notify the firmware when DRM is in charge
drivers/gpu/drm/vc4/vc4_drv.c | 30 +++++++++++++++++++--- include/soc/bcm2835/raspberrypi-firmware.h | 1 + 2 files changed, 27 insertions(+), 4 deletions(-)
The RPI_FIRMWARE_NOTIFY_DISPLAY_DONE firmware call allows to tell the firmware the kernel is in charge of the display now and the firmware can free whatever resources it was using.
Acked-by: Nicolas Saenz Julienne nsaenz@kernel.org Signed-off-by: Maxime Ripard maxime@cerno.tech --- include/soc/bcm2835/raspberrypi-firmware.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h index 73ad784fca96..811ea668c4a1 100644 --- a/include/soc/bcm2835/raspberrypi-firmware.h +++ b/include/soc/bcm2835/raspberrypi-firmware.h @@ -91,6 +91,7 @@ enum rpi_firmware_property_tag { RPI_FIRMWARE_GET_POE_HAT_VAL = 0x00030049, RPI_FIRMWARE_SET_POE_HAT_VAL = 0x00030050, RPI_FIRMWARE_NOTIFY_XHCI_RESET = 0x00030058, + RPI_FIRMWARE_NOTIFY_DISPLAY_DONE = 0x00030066,
/* Dispmanx TAGS */ RPI_FIRMWARE_FRAMEBUFFER_ALLOCATE = 0x00040001,
The bind hooks will modify their controller registers, so simplefb is going to be unusable anyway. Let's avoid any transient state where it could still be in the system but no longer functionnal.
Acked-by: Nicolas Saenz Julienne nsaenz@kernel.org Signed-off-by: Maxime Ripard maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_drv.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 16abc3a3d601..8ab89f805826 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -251,6 +251,10 @@ static int vc4_drm_bind(struct device *dev) if (ret) return ret;
+ ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver); + if (ret) + return ret; + ret = component_bind_all(dev, drm); if (ret) return ret; @@ -259,10 +263,6 @@ static int vc4_drm_bind(struct device *dev) if (ret) goto unbind_all;
- ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver); - if (ret) - goto unbind_all; - ret = vc4_kms_load(drm); if (ret < 0) goto unbind_all;
Hi Maxime
Am 13.12.21 um 10:25 schrieb Maxime Ripard:
The bind hooks will modify their controller registers, so simplefb is going to be unusable anyway. Let's avoid any transient state where it could still be in the system but no longer functionnal.
Acked-by: Nicolas Saenz Julienne nsaenz@kernel.org Signed-off-by: Maxime Ripard maxime@cerno.tech
drivers/gpu/drm/vc4/vc4_drv.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 16abc3a3d601..8ab89f805826 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -251,6 +251,10 @@ static int vc4_drm_bind(struct device *dev)
Since you work on this, I'd like to suggest to call drm_firmware_drivers_only() at the very top of this function. It's our new interface for the kernel's nomodeset argument. If it returns false, the user has disabled native drivers for this boot. The generic DRM driver will continue to run the device.
if (ret) return ret;
- ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver);
- if (ret)
return ret;
There's quite a bit of work being done before calling this function. None of it is allowed to touch HW.
Is that reliable? If so, the code is fine, otherwise the call should go to the top of the function.
Best regards Thomas
ret = component_bind_all(dev, drm); if (ret) return ret; @@ -259,10 +263,6 @@ static int vc4_drm_bind(struct device *dev) if (ret) goto unbind_all;
- ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver);
- if (ret)
goto unbind_all;- ret = vc4_kms_load(drm); if (ret < 0) goto unbind_all;
Am 13.12.21 um 10:47 schrieb Thomas Zimmermann:
Hi Maxime
Am 13.12.21 um 10:25 schrieb Maxime Ripard:
The bind hooks will modify their controller registers, so simplefb is going to be unusable anyway. Let's avoid any transient state where it could still be in the system but no longer functionnal.
Acked-by: Nicolas Saenz Julienne nsaenz@kernel.org Signed-off-by: Maxime Ripard maxime@cerno.tech
drivers/gpu/drm/vc4/vc4_drv.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 16abc3a3d601..8ab89f805826 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -251,6 +251,10 @@ static int vc4_drm_bind(struct device *dev)
Since you work on this, I'd like to suggest to call drm_firmware_drivers_only() at the very top of this function. It's our new interface for the kernel's nomodeset argument. If it returns false,
s/false/true
the user has disabled native drivers for this boot. The generic DRM driver will continue to run the device.
if (ret) return ret; + ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver); + if (ret) + return ret;
There's quite a bit of work being done before calling this function. None of it is allowed to touch HW.
Is that reliable? If so, the code is fine, otherwise the call should go to the top of the function.
Best regards Thomas
ret = component_bind_all(dev, drm); if (ret) return ret; @@ -259,10 +263,6 @@ static int vc4_drm_bind(struct device *dev) if (ret) goto unbind_all; - ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver); - if (ret) - goto unbind_all;
ret = vc4_kms_load(drm); if (ret < 0) goto unbind_all;
Once the call to drm_fb_helper_remove_conflicting_framebuffers() has been made, simplefb has been unregistered and the KMS driver is entirely in charge of the display.
Thus, we can notify the firmware it can free whatever resource it was using to maintain simplefb functional.
Signed-off-by: Maxime Ripard maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_drv.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 8ab89f805826..e26897cb49a9 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -37,6 +37,8 @@ #include <drm/drm_fb_helper.h> #include <drm/drm_vblank.h>
+#include <soc/bcm2835/raspberrypi-firmware.h> + #include "uapi/drm/vc4_drm.h"
#include "vc4_drv.h" @@ -215,6 +217,7 @@ static void vc4_match_add_drivers(struct device *dev, static int vc4_drm_bind(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); + struct rpi_firmware *firmware = NULL; struct drm_device *drm; struct vc4_dev *vc4; struct device_node *node; @@ -251,10 +254,29 @@ static int vc4_drm_bind(struct device *dev) if (ret) return ret;
+ node = of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware"); + if (node) { + firmware = rpi_firmware_get(node); + of_node_put(node); + + if (!firmware) + return -EPROBE_DEFER; + } + ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver); if (ret) return ret;
+ if (firmware) { + ret = rpi_firmware_property(firmware, + RPI_FIRMWARE_NOTIFY_DISPLAY_DONE, + NULL, 0); + if (ret) + drm_warn(drm, "Couldn't stop firmware display driver: %d\n", ret); + + rpi_firmware_put(firmware); + } + ret = component_bind_all(dev, drm); if (ret) return ret;
dri-devel@lists.freedesktop.org
-
Maxime Ripard -
Thomas Zimmermann