* Patch by Greg Ungerer, 19 May 2005:

  add support for the KS8695P (ARM 922 based) CPU

* Patch by Steven Scholz, 19 May 2005:
  Add support for CONFIG_SERIAL_TAG on ARM boards

1 files changed, 205 insertions, 0 deletions

diff --git a/cpu/arm920t/ks8695/lowlevel_init.S b/cpu/arm920t/ks8695/lowlevel_init.S
new file mode 100644
index 0000000..e9f1227
--- /dev/null
+++ b/cpu/arm920t/ks8695/lowlevel_init.S
@@ -0,0 +1,205 @@
+/*
+ *  lowlevel_init.S - basic hardware initialization for the KS8695 CPU
+ *
+ *  Copyright (c) 2004-2005, Greg Ungerer <greg.ungerer@opengear.com>
+ *
+ * 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 <config.h>
+#include <version.h>
+#include <asm/arch/platform.h>
+
+#ifndef CONFIG_SKIP_LOWLEVEL_INIT
+
+/*
+ *************************************************************************
+ *
+ * Handy dandy macros
+ *
+ *************************************************************************
+ */
+
+/* Delay a bit */
+.macro DELAY_FOR cycles, reg0
+	ldr     \reg0, =\cycles
+	subs    \reg0, \reg0, #1
+	subne   pc,  pc, #0xc
+.endm
+
+/*
+ *************************************************************************
+ *
+ * Some local storage.
+ *
+ *************************************************************************
+ */
+
+/* Should we boot with an interactive console or not */
+.globl serial_console
+
+/*
+ *************************************************************************
+ *
+ * Raw hardware initialization code. The important thing is to get
+ * SDRAM setup and running. We do some other basic things here too,
+ * like getting the PLL set for high speed, and init the LEDs.
+ *
+ *************************************************************************
+ */
+
+.globl lowlevel_init
+lowlevel_init:
+
+#if DEBUG
+	/*
+	 * enable UART for early debug trace
+	 */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_UART_DIVISOR)
+	mov	r2, #0xd9
+	str	r2, [r1]		/* 115200 baud */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_UART_LINE_CTRL)
+	mov	r2, #0x03
+	str	r2, [r1]		/* 8 data bits, no parity, 1 stop */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_UART_TX_HOLDING)
+	mov	r2, #0x41
+	str	r2, [r1]		/* write 'A' */
+#endif
+#if DEBUG
+	ldr	r1, =(KS8695_IO_BASE+KS8695_UART_TX_HOLDING)
+	mov	r2, #0x42
+	str	r2, [r1]
+#endif
+
+	/*
+	 * remap the memory and flash regions. we want to end up with
+	 * ram from address 0, and flash at 32MB.
+	 */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_MEM_CTRL0)
+	ldr	r2, =0xbfc00040
+	str	r2, [r1]		/* large flash map */
+	ldr	pc, =(highflash+0x02000000-0x00f00000)	/* jump to high flash address */
+highflash:
+	ldr	r2, =0x8fe00040
+	str	r2, [r1]		/* remap flash range */
+
+	/*
+	 * remap the second select region to the 4MB immediately after
+	 * the first region. This way if you have a larger flash (say 8Mb)
+	 * then you can have it all mapped nicely. Has no effect if you
+	 * only have a 4Mb or smaller flash.
+	 */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_MEM_CTRL1)
+	ldr	r2, =0x9fe40040
+	str	r2, [r1]		/* remap flash2 region, contiguous */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_MEM_GENERAL)
+	ldr	r2, =0x30000005
+	str	r2, [r1]		/* enable both flash selects */
+
+#ifdef CONFIG_CM41xx
+	/*
+	 * map the second flash chip, using the external IO lines.
+	 */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_IO_CTRL0)
+	ldr	r2, =0xafe80b6d
+	str	r2, [r1]		/* remap io0 region, contiguous */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_IO_CTRL1)
+	ldr	r2, =0xbfec0b6d
+	str	r2, [r1]		/* remap io1 region, contiguous */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_MEM_GENERAL)
+	ldr	r2, =0x30050005
+	str	r2, [r1]		/* enable second flash */
+#endif
+
+	/*
+	 * before relocating, we have to setup RAM timing
+	 */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SDRAM_CTRL0)
+#if (PHYS_SDRAM_1_SIZE == 0x02000000)
+	ldr	r2, =0x7fc0000e		/* 32MB */
+#else
+	ldr	r2, =0x3fc0000e		/* 16MB */
+#endif
+	str	r2, [r1]		/* configure sdram bank0 setup */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SDRAM_CTRL1)
+	mov	r2, #0
+	str	r2, [r1]		/* configure sdram bank1 setup */
+
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SDRAM_GENERAL)
+	ldr	r2, =0x0000000a
+	str	r2, [r1]		/* set RAS/CAS timing */
+
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SDRAM_BUFFER)
+	ldr	r2, =0x00030000
+	str	r2, [r1]		/* send NOP command */
+	DELAY_FOR 0x100, r0
+	ldr	r2, =0x00010000
+	str	r2, [r1]		/* send PRECHARGE-ALL */
+	DELAY_FOR 0x100, r0
+
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SDRAM_REFRESH)
+	ldr	r2, =0x00000020
+	str	r2, [r1]		/* set for fast refresh */
+	DELAY_FOR 0x100, r0
+	ldr	r2, =0x00000190
+	str	r2, [r1]		/* set normal refresh timing */
+
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SDRAM_BUFFER)
+	ldr	r2, =0x00020033
+	str	r2, [r1]		/* send mode command */
+	DELAY_FOR 0x100, r0
+	ldr	r2, =0x01f00000
+	str	r2, [r1]		/* enable sdram fifos */
+
+	/*
+	 * set pll to top speed
+	 */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SYSTEN_BUS_CLOCK)
+	mov	r2, #0
+	str	r2, [r1]		/* set pll clock to 166MHz */
+
+	ldr	r1, =(KS8695_IO_BASE+KS8695_SWITCH_CTRL0)
+	ldr	r2, [r1]		/* Get switch ctrl0 register       */
+	and	r2, r2, #0x0fc00000	/* Mask out LED control bits       */
+	orr	r2, r2, #0x01800000	/* Set Link/activity/speed actions */
+	str	r2, [r1]
+
+#ifdef CONFIG_CM4008
+	ldr	r1, =(KS8695_IO_BASE+KS8695_GPIO_MODE)
+	ldr	r2, =0x0000fe30
+	str	r2, [r1]		/* enable LED's as outputs	    */
+	ldr	r1, =(KS8695_IO_BASE+KS8695_GPIO_DATA)
+	ldr	r2, =0x0000fe20
+	str	r2, [r1]		/* turn on power LED		    */
+#endif
+#if defined(CONFIG_CM4008) || defined(CONFIG_CM41xx)
+	ldr	r2, [r1]		/* get current GPIO input data	    */
+	tst	r2, #0x8		/* check if "erase" depressed	    */
+	beq	nobutton
+	mov	r2, #0			/* be quiet on boot, no console	    */
+	ldr	r1, =serial_console
+	str	r2, [r1]
+nobutton:
+#endif
+
+	add	lr, lr, #0x02000000	/* flash is now mapped high */
+	add	ip, ip, #0x02000000	/* this is a hack */
+	mov	pc, lr			/* all done, return */
+
+#endif /* CONFIG_SKIP_LOWLEVEL_INIT */