mainboard: Add preliminary support for A10-based Cubieboard

Add a minimal infrastructure which initializes the system clocks
and serial console.

Change-Id: I768ede6ccf8674ffe9fecd8925cec89768209cab
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/4553
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

5 files changed, 127 insertions, 0 deletions

diff --git a/src/mainboard/cubietech/cubieboard/Kconfig b/src/mainboard/cubietech/cubieboard/Kconfig
new file mode 100644
index 0000000000..72b797e606
--- /dev/null
+++ b/src/mainboard/cubietech/cubieboard/Kconfig
@@ -0,0 +1,29 @@
+if BOARD_CUBIETECH_CUBIEBOARD
+
+config BOARD_SPECIFIC_OPTIONS # dummy
+	def_bool y
+	select ARCH_ARMV7
+	select CPU_ALLWINNER_A10
+	select BOARD_ROMSIZE_KB_4096
+
+config MAINBOARD_DIR
+	string
+	default cubietech/cubieboard
+
+config MAINBOARD_PART_NUMBER
+	string
+	default "Cubieboard A10"
+
+config MAX_CPUS
+	int
+	default 1
+
+config BOOTBLOCK_MAINBOARD_INIT
+	string
+	default "mainboard/cubietech/cubieboard/bootblock.c"
+
+config DRAM_SIZE_MB
+	int
+	default 1024
+
+endif # BOARD_CUBIETECH_CUBIEBOARD
diff --git a/src/mainboard/cubietech/cubieboard/Makefile.inc b/src/mainboard/cubietech/cubieboard/Makefile.inc
new file mode 100644
index 0000000000..29763fb4f6
--- /dev/null
+++ b/src/mainboard/cubietech/cubieboard/Makefile.inc
@@ -0,0 +1 @@
+romstage-y += romstage.c
diff --git a/src/mainboard/cubietech/cubieboard/bootblock.c b/src/mainboard/cubietech/cubieboard/bootblock.c
new file mode 100644
index 0000000000..6e8b751c73
--- /dev/null
+++ b/src/mainboard/cubietech/cubieboard/bootblock.c
@@ -0,0 +1,80 @@
+/*
+ * Minimal bootblock for Cubieboard
+ * It sets up CPU clock, and enables the bootblock console.
+ *
+ * Copyright (C) 2013  Alexandru Gagniuc <mr.nuke.me@gmail.com>
+ * Subject to the GNU GPL v2, or (at your option) any later version.
+ */
+
+#include <arch/io.h>
+#include <uart.h>
+#include <console/console.h>
+#include <cpu/allwinner/a10/gpio.h>
+#include <cpu/allwinner/a10/clock.h>
+
+#define CPU_AHB_APB0_DEFAULT 		\
+	 CPU_CLK_SRC_OSC24M	 	\
+	 | APB0_DIV_1			\
+	 | AHB_DIV_1			\
+	 | AXI_DIV_1
+
+#define GPB22_UART0_TX_FUNC		2
+#define GPB23_UART0_RX_FUNC		2
+
+static void cubieboard_set_sys_clock(void)
+{
+	u32 reg32;
+	struct a10_ccm *ccm = (void *)A1X_CCM_BASE;
+
+	/* Switch CPU clock to main oscillator */
+	write32(CPU_AHB_APB0_DEFAULT, &ccm->cpu_ahb_apb0_cfg);
+
+	/* Configure the PLL1. The value is the same one used by u-boot */
+	write32(0xa1005000, &ccm->pll1_cfg);
+
+	/* FIXME: Delay to wait for PLL to lock */
+	u32 wait = 1000;
+	while (--wait);
+
+	/* Switch CPU to PLL clock */
+	reg32 = read32(&ccm->cpu_ahb_apb0_cfg);
+	reg32 &= ~CPU_CLK_SRC_MASK;
+	reg32 |= CPU_CLK_SRC_PLL1;
+	write32(reg32, &ccm->cpu_ahb_apb0_cfg);
+}
+
+static void cubieboard_setup_clocks(void)
+{
+	struct a10_ccm *ccm = (void *)A1X_CCM_BASE;
+
+	cubieboard_set_sys_clock();
+	/* Configure the clock source for APB1. This drives our UART */
+	write32(APB1_CLK_SRC_OSC24M | APB1_RAT_N(0) | APB1_RAT_M(0),
+		&ccm->apb1_clk_div_cfg);
+
+}
+
+static void cubieboard_setup_gpios(void)
+{
+	/* Mux UART pins */
+	gpio_set_func(GPB, 22, GPB22_UART0_TX_FUNC);
+	gpio_set_func(GPB, 23, GPB23_UART0_RX_FUNC);
+}
+
+static void cubieboard_enable_uart(void)
+{
+	u32 reg32;
+	struct a10_ccm *ccm = (void *)A1X_CCM_BASE;
+	/* Enable clock to UART0 */
+	reg32 = read32(&ccm->apb1_gate);
+	reg32 |= APB1_GATE_UART(0);
+	write32(reg32, &ccm->apb1_gate);
+}
+
+void bootblock_mainboard_init(void);
+void bootblock_mainboard_init(void)
+{
+	cubieboard_setup_clocks();
+	cubieboard_setup_gpios();
+	cubieboard_enable_uart();
+}
diff --git a/src/mainboard/cubietech/cubieboard/devicetree.cb b/src/mainboard/cubietech/cubieboard/devicetree.cb
new file mode 100644
index 0000000000..1358777032
--- /dev/null
+++ b/src/mainboard/cubietech/cubieboard/devicetree.cb
@@ -0,0 +1,3 @@
+chip cpu/allwinner/a10
+	device cpu_cluster 0 on end
+end
diff --git a/src/mainboard/cubietech/cubieboard/romstage.c b/src/mainboard/cubietech/cubieboard/romstage.c
new file mode 100644
index 0000000000..19192cdc40
--- /dev/null
+++ b/src/mainboard/cubietech/cubieboard/romstage.c
@@ -0,0 +1,14 @@
+/*
+ * Placeholder for Cubieboard romstage
+ *
+ * Copyright (C) 2013  Alexandru Gagniuc <mr.nuke.me@gmail.com>
+ * Subject to the GNU GPL v2, or (at your option) any later version.
+ */
+
+#include <console/console.h>
+
+void main(void)
+{
+	console_init();
+	printk(BIOS_INFO, "You have managed to succesfully load romstage.\n");
+}