arch/arm/boards/eukrea_cpuimx35/lowlevel.c

/*
 *
 * (c) 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
 *
 * 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 <init.h>
#include <mach/imx-regs.h>
#include <mach/imx-pll.h>
#include <mach/esdctl.h>
#include <asm/cache-l2x0.h>
#include <asm/io.h>
#include <mach/imx-nand.h>
#include <asm/barebox-arm.h>
#include <asm-generic/memory_layout.h>
#include <asm/system.h>

/* Assuming 24MHz input clock */
#define MPCTL_PARAM_399     (IMX_PLL_PD(0) | IMX_PLL_MFD(15) | IMX_PLL_MFI(8) | IMX_PLL_MFN(5))
#define MPCTL_PARAM_532     ((1 << 31) | IMX_PLL_PD(0) | IMX_PLL_MFD(11) | IMX_PLL_MFI(11) | IMX_PLL_MFN(1))
#define PPCTL_PARAM_300     (IMX_PLL_PD(0) | IMX_PLL_MFD(3) | IMX_PLL_MFI(6) | IMX_PLL_MFN(1))

#ifdef CONFIG_NAND_IMX_BOOT
static void __bare_init __naked insdram(void)
{
	uint32_t r;

	/* Speed up NAND controller by adjusting the NFC divider */
	r = readl(IMX_CCM_BASE + CCM_PDR4);
	r &= ~(0xf << 28);
	r |= 0x1 << 28;
	writel(r, IMX_CCM_BASE + CCM_PDR4);

	/* setup a stack to be able to call imx_nand_load_image() */
	r = STACK_BASE + STACK_SIZE - 12;
	__asm__ __volatile__("mov sp, %0" : : "r"(r));

	imx_nand_load_image((void *)TEXT_BASE, 256 * 1024);

	board_init_lowlevel_return();
}
#endif

void __bare_init __naked board_init_lowlevel(void)
{
	uint32_t r, s;
	unsigned long ccm_base = IMX_CCM_BASE;
#ifdef CONFIG_NAND_IMX_BOOT
	unsigned int *trg, *src;
	int i;
#endif
	register uint32_t loops = 0x20000;

	r = get_cr();
	r |= CR_Z; /* Flow prediction (Z) */
	r |= CR_U; /* unaligned accesses  */
	r |= CR_FI; /* Low Int Latency     */

	__asm__ __volatile__("mrc p15, 0, %0, c1, c0, 1":"=r"(s));
	s |= 0x7;
	__asm__ __volatile__("mcr p15, 0, %0, c1, c0, 1" : : "r"(s));

	set_cr(r);

	r = 0;
	__asm__ __volatile__("mcr p15, 0, %0, c15, c2, 4" : : "r"(r));

	/*
	 * Branch predicition is now enabled.  Flush the BTAC to ensure a valid
	 * starting point.  Don't flush BTAC while it is disabled to avoid
	 * ARM1136 erratum 408023.
	 */
	__asm__ __volatile__("mcr p15, 0, %0, c7, c5, 6" : : "r"(r));

	/* invalidate I cache and D cache */
	__asm__ __volatile__("mcr p15, 0, %0, c7, c7, 0" : : "r"(r));

	/* invalidate TLBs */
	__asm__ __volatile__("mcr p15, 0, %0, c8, c7, 0" : : "r"(r));

	/* Drain the write buffer */
	__asm__ __volatile__("mcr p15, 0, %0, c7, c10, 4" : : "r"(r));

	/* Also setup the Peripheral Port Remap register inside the core */
	r = 0x40000015; /* start from AIPS 2GB region */
	__asm__ __volatile__("mcr p15, 0, %0, c15, c2, 4" : : "r"(r));

	/*
	 * End of ARM1136 init
	 */

	writel(0x003F4208, ccm_base + CCM_CCMR);

	/* Set MPLL , arm clock and ahb clock*/
	writel(MPCTL_PARAM_532, ccm_base + CCM_MPCTL);

	writel(PPCTL_PARAM_300, ccm_base + CCM_PPCTL);
	writel(0x00001000, ccm_base + CCM_PDR0);

	r = readl(ccm_base + CCM_CGR0);
	r |= 0x00300000;
	writel(r, ccm_base + CCM_CGR0);

	r = readl(ccm_base + CCM_CGR1);
	r |= 0x00030C00;
	r |= 0x00000003;
	writel(r, ccm_base + CCM_CGR1);

	r = readl(IMX_L2CC_BASE + L2X0_AUX_CTRL);
	r |= 0x1000;
	writel(r, IMX_L2CC_BASE + L2X0_AUX_CTRL);

	/* Skip SDRAM initialization if we run from RAM */
	r = get_pc();
	if (r > 0x80000000 && r < 0x90000000)
		board_init_lowlevel_return();

	/* Init Mobile DDR */
	writel(0x0000000E, ESDMISC);
	writel(0x00000004, ESDMISC);
	__asm__ volatile ("1:\n"
			"subs %0, %1, #1\n"
			"bne 1b":"=r" (loops):"0" (loops));

	writel(0x0009572B, ESDCFG0);
	writel(0x92220000, ESDCTL0);
	writeb(0xda, IMX_SDRAM_CS0 + 0x400);
	writel(0xA2220000, ESDCTL0);
	writeb(0xda, IMX_SDRAM_CS0);
	writeb(0xda, IMX_SDRAM_CS0);
	writel(0xB2220000, ESDCTL0);
	writeb(0xda, IMX_SDRAM_CS0 + 0x33);
	writeb(0xda, IMX_SDRAM_CS0 + 0x2000000);
	writel(0x82228080, ESDCTL0);

#ifdef CONFIG_NAND_IMX_BOOT
	/* skip NAND boot if not running from NFC space */
	r = get_pc();
	if (r < IMX_NFC_BASE || r > IMX_NFC_BASE + 0x800)
		board_init_lowlevel_return();

	src = (unsigned int *)IMX_NFC_BASE;
	trg = (unsigned int *)TEXT_BASE;

	/* Move ourselves out of NFC SRAM */
	for (i = 0; i < 0x800 / sizeof(int); i++)
		*trg++ = *src++;

	/* Jump to SDRAM */
	r = (unsigned int)&insdram;
	__asm__ __volatile__("mov pc, %0" : : "r"(r));
#else
	board_init_lowlevel_return();
#endif
}