lpc32xx: add support for board work_92105

Work_92105 from Work Microwave is an LPC3250-
based board with the following features:
- 64MB or 128MB SDR DRAM
- 1 GB SLC NAND, managed through MLC controller.
- Ethernet
- Ethernet + PHY SMSC8710
- I2C:
  - EEPROM (24M01-compatible)
  - RTC (DS1374-compatible)
  - Temperature sensor (DS620)
  - DACs (2 x MAX518)
- SPI (through SSP interface)
  - Port expander MAX6957
- LCD display (HD44780-compatible), controlled
  through the port expander and DACs

This board has SPL support, and uses the LPC32XX boot
image format.

Signed-off-by: Albert ARIBAUD (3ADEV) <albert.aribaud@3adev.fr>

1 files changed, 45 insertions, 0 deletions

diff --git a/arch/arm/cpu/arm926ejs/lpc32xx/lowlevel_init.S b/arch/arm/cpu/arm926ejs/lpc32xx/lowlevel_init.S
new file mode 100644
index 0000000..4b8053e
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/lpc32xx/lowlevel_init.S
@@ -0,0 +1,45 @@
+/*
+ * WORK Microwave work_92105 board low level init
+ *
+ * (C) Copyright 2014  DENX Software Engineering GmbH
+ * Written-by: Albert ARIBAUD <albert.aribaud@3adev.fr>
+ *
+ * Low level init is called from SPL to set up the clocks.
+ * On entry, the LPC3250 is in Direct Run mode with all clocks
+ * running at 13 MHz; on exit, ARM clock is 208 MHz, HCLK is
+ * 104 MHz and PCLK is 13 MHz.
+ *
+ * This code must run from SRAM so that the clock changes do
+ * not prevent it from executing.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+.globl lowlevel_init
+
+lowlevel_init:
+
+	/* Set ARM, HCLK, PCLK dividers for normal mode */
+	ldr	r0, =0x0000003D
+	ldr	r1, =0x40004040
+	str	r0, [r1]
+
+	/* Start HCLK PLL for 208 MHz */
+	ldr	r0, =0x0001401E
+	ldr	r1, =0x40004058
+	str	r0, [r1]
+
+	/* wait for HCLK PLL to lock */
+1:
+	ldr	r0, [r1]
+	ands	r0, r0, #1
+	beq	1b
+
+	/* switch to normal mode */
+	ldr	r1, =0x40004044
+	ldr	r0, [r1]
+	orr	r0, #0x00000004
+	str	r0, [r1]
+
+	/* Return to U-boot via saved link register */
+	mov	pc, lr