rockchip: rk3399: Add support for chromebook_kevin

Add support for Kevin, an RK3399-based convertible chromebook that is
very similar to Bob. This patch is mostly based on existing support for
Bob, with only minor changes for Kevin-specific things.

Unlike other Gru boards, coreboot sets Kevin's center logic to 925 mV,
so adjust it here in the dts as well. The rk3399-gru-kevin devicetree
has an unknown event code reference which has to be defined, set it
to the Linux counterpart. The new defconfig is copied from Bob with the
diffconfig:

     DEFAULT_DEVICE_TREE "rk3399-gru-bob" -> "rk3399-gru-kevin"
     DEFAULT_FDT_FILE "rockchip/rk3399-gru-bob.dtb" -> "rockchip/rk3399-gru-kevin.dtb"
     VIDEO_ROCKCHIP_MAX_XRES 1280 -> 2400
     VIDEO_ROCKCHIP_MAX_YRES 800 -> 1600
    +TARGET_CHROMEBOOK_KEVIN y

With this Kevin can boot from SPI flash to a usable U-Boot prompt on the
display with the keyboard working, but cannot boot into Linux for
unknown reasons.

eMMC starts in a working state but fails to re-init, microSD card works
but at a lower-than-expected speed, USB works but causes a hang on
de-init. There are known workarounds to solve eMMC and USB issues.

Cc: Marty E. Plummer <hanetzer@startmail.com>
Cc: Simon Glass <sjg@chromium.org>
[Alper: commit message, resync config with Bob, update MAINTAINERS,
        add to Rockchip doc, add Kconfig help message, set regulator]
Co-developed-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

5 files changed, 27 insertions, 2 deletions

diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index 960f1a9..644ba96 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -137,6 +137,7 @@ dtb-$(CONFIG_ROCKCHIP_RK3399) += \
 	rk3399-ficus.dtb \
 	rk3399-firefly.dtb \
 	rk3399-gru-bob.dtb \
+	rk3399-gru-kevin.dtb \
 	rk3399-khadas-edge.dtb \
 	rk3399-khadas-edge-captain.dtb \
 	rk3399-khadas-edge-v.dtb \
diff --git a/arch/arm/dts/rk3399-gru-kevin-u-boot.dtsi b/arch/arm/dts/rk3399-gru-kevin-u-boot.dtsi
new file mode 100644
index 0000000..c03bd48
--- /dev/null
+++ b/arch/arm/dts/rk3399-gru-kevin-u-boot.dtsi
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Jagan Teki <jagan@amarulasolutions.com>
+ */
+
+#include "rk3399-gru-u-boot.dtsi"
+#include "rk3399-sdram-lpddr3-samsung-4GB-1866.dtsi"
+
+&ppvar_centerlogic_pwm {
+	regulator-init-microvolt = <925000>;
+};
diff --git a/arch/arm/mach-rockchip/rk3399/Kconfig b/arch/arm/mach-rockchip/rk3399/Kconfig
index 17628f9..0833e08 100644
--- a/arch/arm/mach-rockchip/rk3399/Kconfig
+++ b/arch/arm/mach-rockchip/rk3399/Kconfig
@@ -14,6 +14,17 @@ config TARGET_CHROMEBOOK_BOB
 	  display. It includes a Chrome OS EC (Cortex-M3) to provide access to
 	  the keyboard and battery functions.
 
+config TARGET_CHROMEBOOK_KEVIN
+	bool "Samsung Chromebook Plus (RK3399)"
+	select HAS_ROM
+	select ROCKCHIP_SPI_IMAGE
+	help
+	  Kevin is a RK3399-based convertible chromebook. It has two USB 3.0
+	  Type-C ports, 4GB of SDRAM, WiFi and a 12.3" 2400x1600 display. It
+	  uses its USB ports for both power and external display. It includes
+	  a Chromium OS EC (Cortex-M3) to provide access to the keyboard and
+	  battery functions.
+
 config TARGET_EVB_RK3399
 	bool "RK3399 evaluation board"
 	help
diff --git a/arch/arm/mach-rockchip/rk3399/rk3399.c b/arch/arm/mach-rockchip/rk3399/rk3399.c
index d40969c..01a0559 100644
--- a/arch/arm/mach-rockchip/rk3399/rk3399.c
+++ b/arch/arm/mach-rockchip/rk3399/rk3399.c
@@ -140,7 +140,8 @@ void board_debug_uart_init(void)
 	struct rockchip_gpio_regs * const gpio = (void *)GPIO0_BASE;
 
 	if (IS_ENABLED(CONFIG_SPL_BUILD) &&
-	    IS_ENABLED(CONFIG_TARGET_CHROMEBOOK_BOB)) {
+	    (IS_ENABLED(CONFIG_TARGET_CHROMEBOOK_BOB) ||
+	     IS_ENABLED(CONFIG_TARGET_CHROMEBOOK_KEVIN))) {
 		rk_setreg(&grf->io_vsel, 1 << 0);
 
 		/*
diff --git a/arch/arm/mach-rockchip/spl.c b/arch/arm/mach-rockchip/spl.c
index 02c40fb..7a8db63 100644
--- a/arch/arm/mach-rockchip/spl.c
+++ b/arch/arm/mach-rockchip/spl.c
@@ -56,7 +56,8 @@ u32 spl_boot_device(void)
 		defined(CONFIG_TARGET_CHROMEBIT_MICKEY) || \
 		defined(CONFIG_TARGET_CHROMEBOOK_MINNIE) || \
 		defined(CONFIG_TARGET_CHROMEBOOK_SPEEDY) || \
-		defined(CONFIG_TARGET_CHROMEBOOK_BOB)
+		defined(CONFIG_TARGET_CHROMEBOOK_BOB) || \
+		defined(CONFIG_TARGET_CHROMEBOOK_KEVIN)
 	return BOOT_DEVICE_SPI;
 #endif
 	if (CONFIG_IS_ENABLED(ROCKCHIP_BACK_TO_BROM))