The "Display Engine 2.0" (usually called DE2) on the Allwinner A64 SoC is different from the ones on other Allwinner SoCs. It requires a SRAM region to be claimed, otherwise all DE2 subblocks won't be accessible.
Add a bus driver for the Allwinner A64 DE2 part which claims the SRAM region when probing. Signed-off-by: Icenowy Zheng <icen...@aosc.io> --- drivers/bus/Kconfig | 10 ++++++++++ drivers/bus/Makefile | 1 + drivers/bus/sun50i-de2.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 60 insertions(+) create mode 100644 drivers/bus/sun50i-de2.c diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig index ff70850031c5..cc8e4b4b6b59 100644 --- a/drivers/bus/Kconfig +++ b/drivers/bus/Kconfig @@ -95,6 +95,16 @@ config SIMPLE_PM_BUS Controller (BSC, sometimes called "LBSC within Bus Bridge", or "External Bus Interface") as found on several Renesas ARM SoCs. +config SUN50I_DE2_BUS + bool "Allwinner A64 DE2 Bus Driver" + default ARM64 + depends on ARCH_SUNXI + select SUNXI_SRAM + help + Say y here to enable support for Allwinner A64 DE2 bus driver. It's + mostly transparent, but a SRAM region needs to be claimed in the SRAM + controller to make the all blocks in the DE2 part accessible. + config SUNXI_RSB tristate "Allwinner sunXi Reduced Serial Bus Driver" default MACH_SUN8I || MACH_SUN9I || ARM64 diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile index 3d473b8adeac..746ff0cebe10 100644 --- a/drivers/bus/Makefile +++ b/drivers/bus/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_OMAP_INTERCONNECT) += omap_l3_smx.o omap_l3_noc.o obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o obj-$(CONFIG_QCOM_EBI2) += qcom-ebi2.o +obj-$(CONFIG_SUN50I_DE2_BUS) += sun50i-de2.o obj-$(CONFIG_SUNXI_RSB) += sunxi-rsb.o obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o obj-$(CONFIG_TEGRA_ACONNECT) += tegra-aconnect.o diff --git a/drivers/bus/sun50i-de2.c b/drivers/bus/sun50i-de2.c new file mode 100644 index 000000000000..836828ef96d5 --- /dev/null +++ b/drivers/bus/sun50i-de2.c @@ -0,0 +1,49 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Allwinner A64 Display Engine 2.0 Bus Driver + * + * Copyright (C) 2018 Icenowy Zheng <icen...@aosc.io> + */ + +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/soc/sunxi/sunxi_sram.h> + +static int sun50i_de2_bus_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + int ret; + + ret = sunxi_sram_claim(&pdev->dev); + if (ret) { + dev_err(&pdev->dev, "Error couldn't map SRAM to device\n"); + return ret; + } + + if (np) + of_platform_populate(np, NULL, NULL, &pdev->dev); + + return 0; +} + +static int sun50i_de2_bus_remove(struct platform_device *pdev) +{ + sunxi_sram_release(&pdev->dev); + return 0; +} + +static const struct of_device_id sun50i_de2_bus_of_match[] = { + { .compatible = "allwinner,sun50i-a64-de2", }, + { /* sentinel */ } +}; + +static struct platform_driver sun50i_de2_bus_driver = { + .probe = sun50i_de2_bus_probe, + .remove = sun50i_de2_bus_remove, + .driver = { + .name = "sun50i-de2-bus", + .of_match_table = sun50i_de2_bus_of_match, + }, +}; + +builtin_platform_driver(sun50i_de2_bus_driver); -- 2.15.1