This adds display sharing support in tidss display driver along with an
example overlay devicetree file using which can be used to enable display
sharing on AM62x devices with device manager core i.e. R5F expected to run
a custom firmware which supports corresponding display sharing
configuration.
As resources can be partitioned at different levels a flexible scheme is
followed while designing devicetree bindings and driver changes keeping in
mind possible scenarios in which resources can be partitioned and various
DSS hardware IP's supported across different devices.
A rebased version of this patch has been tested on AM62P SoC which also
supports same DSS IP as AM62x and the patch with display sharing
functionality is already available in vendor-specific kernel source tree
[1] along with documentation which explains the design [2] and DM firmware
support [3].
NOTE1: This is marked as RFC for upstream since AM62P is not yet supported
in upstream tree and for AM62x SoC which is the target SoC for this patch,
the dss sharing functionality is not validated on upstream tree due to
missing OLDI support and display sharing DM firmware support, but we still
wanted to get some feedback on this.
NOTE2: This series depends on :
https://lore.kernel.org/all/[email protected]/
[1] :
https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/?h=09.01.00.007&id=d805270609cfb6b2e67bd2fd5959d71f48393196
https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/?h=09.01.00.007&id=93d751a94cbf9ad07c7f658e78aa510d919d7cd6
https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/?h=09.01.00.007&id=665c17837dc8bed27e8d63388f8f7f7a85c0cd94
https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/commit/?h=ti-linux-6.1.y-cicd&id=f8d7f1a9617862af922c6bc10e0765ba4f4857d6
[2] :
https://software-dl.ti.com/processor-sdk-linux/esd/AM62PX/09_01_00_08/exports/docs/linux/Foundational_Components/Kernel/Kernel_Drivers/Display/DSS7.html#driver-features
(Display Sharing mode feature description)
https://software-dl.ti.com/processor-sdk-linux/esd/AM62PX/09_01_00_08/exports/docs/linux/How_to_Guides/Target/How_to_enable_display_sharing_between_remotecore_and_Linux.html
(How To Guide)
https://software-dl.ti.com/processor-sdk-linux/esd/AM62PX/09_01_00_08/exports/docs/system/Demo_User_Guides/Display_Cluster_User_Guide.html
(Display Cluster user guide with demo details)
[3] :
https://git.ti.com/cgit/processor-firmware/ti-linux-firmware/tree/ti-dm/am62pxx/dss_display_share.wkup-r5f0_0.release.strip.out?h=ti-linux-firmware-next
Devarsh Thakkar (3):
dt-bindings: display: ti,am65x-dss: Add support for display sharing
mode
drm/tidss: Add support for display sharing
arm64: dts: ti: k3-am62x: Add overlay to use DSS in display sharing
mode
.../bindings/display/ti/ti,am65x-dss.yaml | 82 ++++++
arch/arm64/boot/dts/ti/Makefile | 1 +
.../dts/ti/k3-am62x-sk-dss-shared-mode.dtso | 23 ++
drivers/gpu/drm/tidss/tidss_crtc.c | 120 ++++++++-
drivers/gpu/drm/tidss/tidss_dispc.c | 254 ++++++++++++++++--
drivers/gpu/drm/tidss/tidss_dispc.h | 2 +-
drivers/gpu/drm/tidss/tidss_drv.c | 33 ++-
drivers/gpu/drm/tidss/tidss_drv.h | 6 +
8 files changed, 481 insertions(+), 40 deletions(-)
create mode 100644 arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
--
2.34.1
This overlay needs to be used with display sharing supported device
manager firmware only.
Remote core running this firmware has write access to "common" register
space, VIDL pipeline, OVR1 overlay and VP1 videoport.
The processing core running Linux is provided write access to VID
pipeline and "common1" register space.
The VP1 video port is shared between Linux and remote core with remote
core configuring the overlay manager to set Zorder 1 for VID pipeline
and Zorder 2 for VIDL pipeline.
Add reserved memory region for framebuffer region used by remote core in
dss shared mode overlay file so that Linux does not re-use the same
while allocating memory.
Also add a label for reserved memory region in base device-tree file so
that it can be referred back in overlay file.
Signed-off-by: Devarsh Thakkar <[email protected]>
---
arch/arm64/boot/dts/ti/Makefile | 1 +
.../arm64/boot/dts/ti/k3-am62x-sk-common.dtsi | 2 +-
.../dts/ti/k3-am62x-sk-dss-shared-mode.dtso | 33 +++++++++++++++++++
3 files changed, 35 insertions(+), 1 deletion(-)
create mode 100644 arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
diff --git a/arch/arm64/boot/dts/ti/Makefile b/arch/arm64/boot/dts/ti/Makefile
index 52c1dc910308..ff832741b367 100644
--- a/arch/arm64/boot/dts/ti/Makefile
+++ b/arch/arm64/boot/dts/ti/Makefile
@@ -35,6 +35,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-ov5640.dtbo
dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-tevi-ov5640.dtbo
dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-imx219.dtbo
dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-hdmi-audio.dtbo
+dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-dss-shared-mode.dtbo
# Boards with AM64x SoC
dtb-$(CONFIG_ARCH_K3) += k3-am642-evm.dtb
diff --git a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
index 33768c02d8eb..8b55ca10102f 100644
--- a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
@@ -34,7 +34,7 @@ memory@80000000 {
reg = <0x00000000 0x80000000 0x00000000 0x80000000>;
};
- reserved-memory {
+ reserved_memory: reserved-memory {
#address-cells = <2>;
#size-cells = <2>;
ranges;
diff --git a/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso b/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
new file mode 100644
index 000000000000..02153748a5c2
--- /dev/null
+++ b/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0
+/**
+ * DT overlay to enable display sharing mode for AM62P DSS0
+ * This is compatible with custom AM62 Device Manager firmware
+ *
+ * Copyright (C) 2023 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+&dss0 {
+ ti,dss-shared-mode;
+ ti,dss-shared-mode-vp = "vp1";
+ ti,dss-shared-mode-vp-owned = <0>;
+ ti,dss-shared-mode-common = "common1";
+ ti,dss-shared-mode-planes = "vid";
+ ti,dss-shared-mode-plane-zorder = <0>;
+ interrupts = <GIC_SPI 85 IRQ_TYPE_LEVEL_HIGH>;
+};
+
+&reserved_memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ rtos_framebuffer_memory_region: rtos-framebuffer-memory@94800000 {
+ compatible = "shared-dma-pool";
+ reg = <0x00 0x94800000 0x00 0x08000000>;
+ no-map;
+ };
+};
--
2.34.1
Hi,
On 16/01/2024 15:41, Devarsh Thakkar wrote:
> This overlay needs to be used with display sharing supported device
> manager firmware only.
>
> Remote core running this firmware has write access to "common" register
> space, VIDL pipeline, OVR1 overlay and VP1 videoport.
>
> The processing core running Linux is provided write access to VID
> pipeline and "common1" register space.
>
> The VP1 video port is shared between Linux and remote core with remote
> core configuring the overlay manager to set Zorder 1 for VID pipeline
> and Zorder 2 for VIDL pipeline.
>
> Add reserved memory region for framebuffer region used by remote core in
> dss shared mode overlay file so that Linux does not re-use the same
> while allocating memory.
I don't understand this one. Why is RAM used by RTOS accessible by Linux
in the first place?
Tomi
> Also add a label for reserved memory region in base device-tree file so
> that it can be referred back in overlay file.
>
> Signed-off-by: Devarsh Thakkar <[email protected]>
> ---
> arch/arm64/boot/dts/ti/Makefile | 1 +
> .../arm64/boot/dts/ti/k3-am62x-sk-common.dtsi | 2 +-
> .../dts/ti/k3-am62x-sk-dss-shared-mode.dtso | 33 +++++++++++++++++++
> 3 files changed, 35 insertions(+), 1 deletion(-)
> create mode 100644 arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
>
> diff --git a/arch/arm64/boot/dts/ti/Makefile b/arch/arm64/boot/dts/ti/Makefile
> index 52c1dc910308..ff832741b367 100644
> --- a/arch/arm64/boot/dts/ti/Makefile
> +++ b/arch/arm64/boot/dts/ti/Makefile
> @@ -35,6 +35,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-ov5640.dtbo
> dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-tevi-ov5640.dtbo
> dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-imx219.dtbo
> dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-hdmi-audio.dtbo
> +dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-dss-shared-mode.dtbo
>
> # Boards with AM64x SoC
> dtb-$(CONFIG_ARCH_K3) += k3-am642-evm.dtb
> diff --git a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
> index 33768c02d8eb..8b55ca10102f 100644
> --- a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
> @@ -34,7 +34,7 @@ memory@80000000 {
> reg = <0x00000000 0x80000000 0x00000000 0x80000000>;
> };
>
> - reserved-memory {
> + reserved_memory: reserved-memory {
> #address-cells = <2>;
> #size-cells = <2>;
> ranges;
> diff --git a/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso b/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
> new file mode 100644
> index 000000000000..02153748a5c2
> --- /dev/null
> +++ b/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
> @@ -0,0 +1,33 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/**
> + * DT overlay to enable display sharing mode for AM62P DSS0
> + * This is compatible with custom AM62 Device Manager firmware
> + *
> + * Copyright (C) 2023 Texas Instruments Incorporated - http://www.ti.com/
> + */
> +
> +/dts-v1/;
> +/plugin/;
> +
> +#include <dt-bindings/interrupt-controller/irq.h>
> +#include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> +&dss0 {
> + ti,dss-shared-mode;
> + ti,dss-shared-mode-vp = "vp1";
> + ti,dss-shared-mode-vp-owned = <0>;
> + ti,dss-shared-mode-common = "common1";
> + ti,dss-shared-mode-planes = "vid";
> + ti,dss-shared-mode-plane-zorder = <0>;
> + interrupts = <GIC_SPI 85 IRQ_TYPE_LEVEL_HIGH>;
> +};
> +
> +&reserved_memory {
> + #address-cells = <2>;
> + #size-cells = <2>;
> + rtos_framebuffer_memory_region: rtos-framebuffer-memory@94800000 {
> + compatible = "shared-dma-pool";
> + reg = <0x00 0x94800000 0x00 0x08000000>;
> + no-map;
> + };
> +};
Hi Tomi,
Thanks for the review.
On 23/01/24 13:59, Tomi Valkeinen wrote:
> Hi,
>
> On 16/01/2024 15:41, Devarsh Thakkar wrote:
>> This overlay needs to be used with display sharing supported device
>> manager firmware only.
>>
>> Remote core running this firmware has write access to "common" register
>> space, VIDL pipeline, OVR1 overlay and VP1 videoport.
>>
>> The processing core running Linux is provided write access to VID
>> pipeline and "common1" register space.
>>
>> The VP1 video port is shared between Linux and remote core with remote
>> core configuring the overlay manager to set Zorder 1 for VID pipeline
>> and Zorder 2 for VIDL pipeline.
>>
>> Add reserved memory region for framebuffer region used by remote core in
>> dss shared mode overlay file so that Linux does not re-use the same
>> while allocating memory.
>
> I don't understand this one. Why is RAM used by RTOS accessible by Linux
> in the first place?
>
Well, I think the R5 SPL initializes full DDR before starting firmwares
on remote cores and the regions used by this remote cores be it for IPC
or Code/data are marked as reserved both in Linux as well as U-boot so
that Linux/U-boot does not use it [1].
Same scheme is followed here w.r. t RTOS framebuffer too.
[1] :
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi?h=v6.7#n63
Regards
Devarsh
> Tomi
>
>> Also add a label for reserved memory region in base device-tree file so
>> that it can be referred back in overlay file.
>>
>> Signed-off-by: Devarsh Thakkar <[email protected]>
>> ---
>> arch/arm64/boot/dts/ti/Makefile | 1 +
>> .../arm64/boot/dts/ti/k3-am62x-sk-common.dtsi | 2 +-
>> .../dts/ti/k3-am62x-sk-dss-shared-mode.dtso | 33 +++++++++++++++++++
>> 3 files changed, 35 insertions(+), 1 deletion(-)
>> create mode 100644
>> arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
>>
>> diff --git a/arch/arm64/boot/dts/ti/Makefile
>> b/arch/arm64/boot/dts/ti/Makefile
>> index 52c1dc910308..ff832741b367 100644
>> --- a/arch/arm64/boot/dts/ti/Makefile
>> +++ b/arch/arm64/boot/dts/ti/Makefile
>> @@ -35,6 +35,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-ov5640.dtbo
>> dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-tevi-ov5640.dtbo
>> dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-csi2-imx219.dtbo
>> dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-hdmi-audio.dtbo
>> +dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-dss-shared-mode.dtbo
>> # Boards with AM64x SoC
>> dtb-$(CONFIG_ARCH_K3) += k3-am642-evm.dtb
>> diff --git a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
>> b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
>> index 33768c02d8eb..8b55ca10102f 100644
>> --- a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
>> +++ b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
>> @@ -34,7 +34,7 @@ memory@80000000 {
>> reg = <0x00000000 0x80000000 0x00000000 0x80000000>;
>> };
>> - reserved-memory {
>> + reserved_memory: reserved-memory {
>> #address-cells = <2>;
>> #size-cells = <2>;
>> ranges;
>> diff --git a/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
>> b/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
>> new file mode 100644
>> index 000000000000..02153748a5c2
>> --- /dev/null
>> +++ b/arch/arm64/boot/dts/ti/k3-am62x-sk-dss-shared-mode.dtso
>> @@ -0,0 +1,33 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/**
>> + * DT overlay to enable display sharing mode for AM62P DSS0
>> + * This is compatible with custom AM62 Device Manager firmware
>> + *
>> + * Copyright (C) 2023 Texas Instruments Incorporated -
>> http://www.ti.com/
>> + */
>> +
>> +/dts-v1/;
>> +/plugin/;
>> +
>> +#include <dt-bindings/interrupt-controller/irq.h>
>> +#include <dt-bindings/interrupt-controller/arm-gic.h>
>> +
>> +&dss0 {
>> + ti,dss-shared-mode;
>> + ti,dss-shared-mode-vp = "vp1";
>> + ti,dss-shared-mode-vp-owned = <0>;
>> + ti,dss-shared-mode-common = "common1";
>> + ti,dss-shared-mode-planes = "vid";
>> + ti,dss-shared-mode-plane-zorder = <0>;
>> + interrupts = <GIC_SPI 85 IRQ_TYPE_LEVEL_HIGH>;
>> +};
>> +
>> +&reserved_memory {
>> + #address-cells = <2>;
>> + #size-cells = <2>;
>> + rtos_framebuffer_memory_region: rtos-framebuffer-memory@94800000 {
>> + compatible = "shared-dma-pool";
>> + reg = <0x00 0x94800000 0x00 0x08000000>;
>> + no-map;
>> + };
>> +};
>
>