WIP: Initial support for Samsung Exynos 5250 ARM CPU

Samsung SoC files, including Exynos5 (a Cortex-A15
implementation). Since this is an SoC we'll forego the x86-style
{north,south}bridge and cpu distinction. We may try to split some
stuff out before the final version if prudent.

Change-Id: Ie068e9dc3dd836c83d90e282b10d5202e7a4ba9b
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: http://review.coreboot.org/2005
Tested-by: build bot (Jenkins)

1 files changed, 120 insertions, 0 deletions

diff --git a/src/cpu/samsung/exynos5250/lowlevel_init_c.c b/src/cpu/samsung/exynos5250/lowlevel_init_c.c
new file mode 100644
index 0000000000..2215fb7a95
--- /dev/null
+++ b/src/cpu/samsung/exynos5250/lowlevel_init_c.c
@@ -0,0 +1,120 @@
+/*
+ * Lowlevel setup for SMDK5250 board based on S5PC520
+ *
+ * Copyright (C) 2012 Samsung Electronics
+ * Copyright (c) 2012 The Chromium OS Authors.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <config.h>
+#include <cpu/samsung/exynos5-common/exynos5-common.h>
+#include <cpu/samsung/exynos5-common/spl.h>
+#include <cpu/samsung/exynos5250/clock_init.h>
+#include <cpu/samsung/exynos5250/cpu.h>
+#include <cpu/samsung/exynos5250/dmc.h>
+#include <cpu/samsung/exynos5250/pinmux.h>
+#include <cpu/samsung/exynos5250/power.h>
+#include <cpu/samsung/exynos5250/setup.h>
+#include <cpu/samsung/exynos5250/tzpc.h>
+#include "setup.h"
+
+
+void do_barriers(void);	/* FIXME: make gcc shut up about "no previous prototype" */
+
+void do_barriers(void)
+{
+	/*
+	 * The reason we don't write out the instructions dsb/isb/sev:
+	 * While ARM Cortex-A8 supports ARM v7 instruction set (-march=armv7a),
+	 * we compile with -march=armv5 to allow more compilers to work.
+	 * For U-Boot code this has no performance impact.
+	 */
+	__asm__ __volatile__(
+#if defined(__thumb__)
+	".hword 0xF3BF, 0x8F4F\n"  /* dsb; darn -march=armv5 */
+	".hword 0xF3BF, 0x8F6F\n"  /* isb; darn -march=armv5 */
+	".hword 0xBF40\n"          /* sev; darn -march=armv5 */
+#else
+	".word  0xF57FF04F\n"      /* dsb; darn -march=armv5 */
+	".word  0xF57FF06F\n"      /* isb; darn -march=armv5 */
+	".word  0xE320F004\n"      /* sev; darn -march=armv5 */
+#endif
+	);
+}
+
+/* These are the things we can do during low-level init */
+enum {
+	DO_WAKEUP	= 1 << 0,
+	DO_UART		= 1 << 1,
+	DO_CLOCKS	= 1 << 2,
+	DO_POWER	= 1 << 3,
+};
+
+int lowlevel_init_subsystems(void)
+{
+	uint32_t reset_status;
+	int actions = 0;
+
+	do_barriers();
+
+	/* Setup cpu info which is needed to select correct register offsets */
+	cpu_info_init();
+
+	reset_status = power_read_reset_status();
+
+	switch (reset_status) {
+	case S5P_CHECK_SLEEP:
+		actions = DO_CLOCKS | DO_WAKEUP;
+		break;
+	case S5P_CHECK_DIDLE:
+	case S5P_CHECK_LPA:
+		actions = DO_WAKEUP;
+	default:
+		/* This is a normal boot (not a wake from sleep) */
+		actions = DO_UART | DO_CLOCKS | DO_POWER;
+	}
+
+	if (actions & DO_POWER)
+		power_init();
+	if (actions & DO_CLOCKS)
+		system_clock_init();
+	if (actions & DO_UART) {
+		/* Set up serial UART so we can printf() */
+//		exynos_pinmux_config(EXYNOS_UART, PINMUX_FLAG_NONE);
+		/* FIXME(dhendrix): add a function for mapping
+		   CONFIG_CONSOLE_SERIAL_UART_ADDRESS to PERIPH_ID_UARTn */
+		exynos_pinmux_config(PERIPH_ID_UART3, PINMUX_FLAG_NONE);
+		/* FIXME(dhendrix): serial_init() does not seem to
+		   actually do anything !?!? */
+//		serial_init();
+		init_timer();	/* FIXME(dhendrix): was timer_init() */
+	}
+
+/* FIXME(dhendrix): place this somewhere for ramstage... */
+#if 0
+	if (actions & DO_CLOCKS) {
+		mem_ctrl_init();
+		tzpc_init();
+	}
+#endif
+
+	return actions & DO_WAKEUP;
+}