board: Add support for the CMF Phone (1)

This device has a broken framebuffer. As such, logs are passed via UART.

Signed-off-by: Igor Belwon <igor.belwon@mentallysanemainliners.org>

board/Kconfig

@@ -21,6 +21,23 @@ menu "Device Support"
 		help
 		  Say Y if you want to include support for Pixel 2 XL
 
+	config NOTHING_TETRIS
+		bool "Support for CMF Phone 1"
+		default n
+		depends on MT6878
+		help
+		  Say Y if you want to include support for CMF Phone 1
+
+	config NOTHING_TETRIS_DISABLE_WDT
+		bool "Disable the watchdog timer on startup"
+		default y
+		depends on NOTHING_TETRIS
+		help
+		  Say Y if you want to disable the watchdog timer on startup
+		  on this board. While this is obviously useful for end-users,
+		  developers may want to leave this on to avoid holding down
+		  the power button every time.
+
 	config QEMU_BOARD_VIRT
 		bool "Support for QEMU virt platform (aarch64)"
 		default n
@@ -157,6 +174,7 @@ menu "Device Specific Addresses"
 
 	config PAYLOAD_ENTRY
 		hex "Payload Entry Address"
+		default 0x50000000 if NOTHING_TETRIS
 		default 0x050000000 if SAMSUNG_J4LTE
 		default 0x090000000 if SAMSUNG_J5LTE
 		default 0x090000000 if SAMSUNG_GTA4XL
@@ -164,6 +182,7 @@ menu "Device Specific Addresses"
 
 	config RAMDISK_ENTRY
 		hex "Ramdisk Entry Address"
+		default 0x40000000 if NOTHING_TETRIS
 		default 0x084000000 if SAMSUNG_GTA4XL
 		default 0x51100000 if VOLLA_ALGIZ
 

board/Makefile

@@ -1,6 +1,7 @@
 lib-$(CONFIG_APPLE_N61AP) += apple/board-n61ap.o
 lib-$(CONFIG_AMAZON_PW3) += amazon/board-pw3.o
 lib-$(CONFIG_GOOGLE_TAIMEN) += google/board-taimen.o
+lib-$(CONFIG_NOTHING_TETRIS) += nothing/board-tetris.o
 lib-$(CONFIG_QEMU_BOARD_VIRT) += qemu/board-virt.o
 lib-$(CONFIG_SAMSUNG_A105F) += samsung/board-a105f.o
 lib-$(CONFIG_SAMSUNG_A127F) += samsung/board-a127f.o

board/nothing/board-tetris.c

@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2025, Igor Belwon <igor.belwon@mentallysanemainliners.org>
+ */
+#include <board.h>
+#include <drivers/framework.h>
+#include <lib/debug.h>
+
+#define UART_BASE		0x11001000
+
+#define UART_LSR_BASE	0x14
+#define UART_LSR_DR 	0x01 	/* Data ready */
+#define UART_LSR_THRE 	0x20 	/* TX holding register empty */
+
+#define WDT_BASE		0x1c00a000
+#define WDT_MODE_KEY	0x22000000
+#define WDT_MODE_EN		(1 << 0)
+
+void uart_putc(char ch)
+{
+	/* wait until TX is ready */
+	while (!(readl((void *)(UART_BASE + UART_LSR_BASE)) & UART_LSR_THRE))
+		;
+
+	writel(ch, (void *)UART_BASE); // thr is at offset 0x0, which is just uart_base
+}
+
+void uart_puts(const char *s)
+{
+	while (*s != '\0') {
+		uart_putc(*s);
+		s++;
+	}
+}
+
+void tetris_disable_wdt(void)
+{
+	uint32_t reg;
+
+	reg = readl((void*)WDT_BASE);
+	if (reg & WDT_MODE_EN)
+	{
+		reg &= ~WDT_MODE_EN;
+		reg |= WDT_MODE_KEY;
+		writel(reg, (void*)WDT_BASE);
+		printk(KERN_INFO, "%s: disabled watchdog timer.\n", __func__);
+	}
+	else
+		printk(KERN_ERR, "%s: watchdog is already disabled.\n", __func__);
+
+	return;
+}
+
+int tetris_init(void)
+{
+	return 0;
+}
+
+int tetris_drv(void)
+{
+	return 0;
+}
+
+int tetris_late_init(void)
+{
+#ifdef CONFIG_NOTHING_TETRIS_DISABLE_WDT
+	tetris_disable_wdt();
+#endif
+	return 0;
+}
+
+struct board_data board_ops = {
+	.name = "cmf-phone-1",
+	.ops = {
+		.early_init = tetris_init,
+		.drivers_init = tetris_drv,
+		.late_init = tetris_late_init,
+	},
+	.quirks = 0
+};

configs/tetris_defconfig

@@ -0,0 +1,11 @@
+CONFIG_POSITION_INDEPENDENT=y
+# CONFIG_COMPRESS_GZIP is not set
+CONFIG_COMPRESS_LZ4=y
+# CONFIG_SIMPLE_FB is not set
+CONFIG_UART_DEBUG=y
+CONFIG_MT6878=y
+CONFIG_NOTHING_TETRIS=y
+CONFIG_NOTHING_TETRIS_DISABLE_WDT=y
+CONFIG_TEXT_BASE=0x40000000
+CONFIG_PAYLOAD_ENTRY=0x60000000
+CONFIG_RAMDISK_ENTRY=0x51100000