MX51: Add initial support for the Freescale MX51

The patch add initial support for the Freescale i.MX51 processor
(family arm cortex_a8).

Signed-off-by: Stefano Babic <sbabic@denx.de>
Signed-off-by: Fred Fan <fanyefeng@gmail.com>

1 files changed, 293 insertions, 0 deletions

diff --git a/cpu/arm_cortexa8/mx51/clock.c b/cpu/arm_cortexa8/mx51/clock.c
new file mode 100644
index 0000000000..3c6f0c08ad
--- /dev/null
+++ b/cpu/arm_cortexa8/mx51/clock.c
@@ -0,0 +1,293 @@
+/*
+ * (C) Copyright 2007
+ * Sascha Hauer, Pengutronix
+ *
+ * (C) Copyright 2009 Freescale Semiconductor, Inc.
+ *
+ * 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 <asm/io.h>
+#include <asm/errno.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/crm_regs.h>
+
+enum pll_clocks {
+	PLL1_CLOCK = 0,
+	PLL2_CLOCK,
+	PLL3_CLOCK,
+	PLL_CLOCKS,
+};
+
+struct mxc_pll_reg *mxc_plls[PLL_CLOCKS] = {
+	[PLL1_CLOCK] = (struct mxc_pll_reg *)PLL1_BASE_ADDR,
+	[PLL2_CLOCK] = (struct mxc_pll_reg *)PLL2_BASE_ADDR,
+	[PLL3_CLOCK] = (struct mxc_pll_reg *)PLL3_BASE_ADDR,
+};
+
+struct mxc_ccm_reg *mxc_ccm = MXC_CCM_BASE;
+
+/*
+ * Calculate the frequency of this pll.
+ */
+static u32 decode_pll(struct mxc_pll_reg *pll, u32 infreq)
+{
+	u32 mfi, mfn, mfd, pd;
+
+	mfn = __raw_readl(&pll->mfn);
+	mfd = __raw_readl(&pll->mfd) + 1;
+	mfi = __raw_readl(&pll->op);
+	pd = (mfi  & 0xF) + 1;
+	mfi = (mfi >> 4) & 0xF;
+	mfi = (mfi >= 5) ? mfi : 5;
+
+	return ((4 * (infreq / 1000) * (mfi * mfd + mfn)) / (mfd * pd)) * 1000;
+}
+
+/*
+ * Get mcu main rate
+ */
+u32 get_mcu_main_clk(void)
+{
+	u32 reg, freq;
+
+	reg = (__raw_readl(&mxc_ccm->cacrr) & MXC_CCM_CACRR_ARM_PODF_MASK) >>
+		MXC_CCM_CACRR_ARM_PODF_OFFSET;
+	freq = decode_pll(mxc_plls[PLL1_CLOCK], CONFIG_MX51_HCLK_FREQ);
+	return freq / (reg + 1);
+}
+
+/*
+ * Get the rate of peripheral's root clock.
+ */
+static u32 get_periph_clk(void)
+{
+	u32 reg;
+
+	reg = __raw_readl(&mxc_ccm->cbcdr);
+	if (!(reg & MXC_CCM_CBCDR_PERIPH_CLK_SEL))
+		return decode_pll(mxc_plls[PLL2_CLOCK], CONFIG_MX51_HCLK_FREQ);
+	reg = __raw_readl(&mxc_ccm->cbcmr);
+	switch ((reg & MXC_CCM_CBCMR_PERIPH_CLK_SEL_MASK) >>
+		MXC_CCM_CBCMR_PERIPH_CLK_SEL_OFFSET) {
+	case 0:
+		return decode_pll(mxc_plls[PLL1_CLOCK], CONFIG_MX51_HCLK_FREQ);
+	case 1:
+		return decode_pll(mxc_plls[PLL3_CLOCK], CONFIG_MX51_HCLK_FREQ);
+	default:
+		return 0;
+	}
+	/* NOTREACHED */
+}
+
+/*
+ * Get the rate of ipg clock.
+ */
+static u32 get_ipg_clk(void)
+{
+	u32 ahb_podf, ipg_podf;
+
+	ahb_podf = __raw_readl(&mxc_ccm->cbcdr);
+	ipg_podf = (ahb_podf & MXC_CCM_CBCDR_IPG_PODF_MASK) >>
+			MXC_CCM_CBCDR_IPG_PODF_OFFSET;
+	ahb_podf = (ahb_podf & MXC_CCM_CBCDR_AHB_PODF_MASK) >>
+			MXC_CCM_CBCDR_AHB_PODF_OFFSET;
+	return get_periph_clk() / ((ahb_podf + 1) * (ipg_podf + 1));
+}
+
+/*
+ * Get the rate of ipg_per clock.
+ */
+static u32 get_ipg_per_clk(void)
+{
+	u32 pred1, pred2, podf;
+
+	if (__raw_readl(&mxc_ccm->cbcmr) & MXC_CCM_CBCMR_PERCLK_IPG_CLK_SEL)
+		return get_ipg_clk();
+	/* Fixme: not handle what about lpm*/
+	podf = __raw_readl(&mxc_ccm->cbcdr);
+	pred1 = (podf & MXC_CCM_CBCDR_PERCLK_PRED1_MASK) >>
+		MXC_CCM_CBCDR_PERCLK_PRED1_OFFSET;
+	pred2 = (podf & MXC_CCM_CBCDR_PERCLK_PRED2_MASK) >>
+		MXC_CCM_CBCDR_PERCLK_PRED2_OFFSET;
+	podf = (podf & MXC_CCM_CBCDR_PERCLK_PODF_MASK) >>
+		MXC_CCM_CBCDR_PERCLK_PODF_OFFSET;
+
+	return get_periph_clk() / ((pred1 + 1) * (pred2 + 1) * (podf + 1));
+}
+
+/*
+ * Get the rate of uart clk.
+ */
+static u32 get_uart_clk(void)
+{
+	unsigned int freq, reg, pred, podf;
+
+	reg = __raw_readl(&mxc_ccm->cscmr1);
+	switch ((reg & MXC_CCM_CSCMR1_UART_CLK_SEL_MASK) >>
+		MXC_CCM_CSCMR1_UART_CLK_SEL_OFFSET) {
+	case 0x0:
+		freq = decode_pll(mxc_plls[PLL1_CLOCK],
+				    CONFIG_MX51_HCLK_FREQ);
+		break;
+	case 0x1:
+		freq = decode_pll(mxc_plls[PLL2_CLOCK],
+				    CONFIG_MX51_HCLK_FREQ);
+		break;
+	case 0x2:
+		freq = decode_pll(mxc_plls[PLL3_CLOCK],
+				    CONFIG_MX51_HCLK_FREQ);
+		break;
+	default:
+		return 66500000;
+	}
+
+	reg = __raw_readl(&mxc_ccm->cscdr1);
+
+	pred = (reg & MXC_CCM_CSCDR1_UART_CLK_PRED_MASK) >>
+		MXC_CCM_CSCDR1_UART_CLK_PRED_OFFSET;
+
+	podf = (reg & MXC_CCM_CSCDR1_UART_CLK_PODF_MASK) >>
+		MXC_CCM_CSCDR1_UART_CLK_PODF_OFFSET;
+	freq /= (pred + 1) * (podf + 1);
+
+	return freq;
+}
+
+/*
+ * This function returns the low power audio clock.
+ */
+u32 get_lp_apm(void)
+{
+	u32 ret_val = 0;
+	u32 ccsr = __raw_readl(&mxc_ccm->ccsr);
+
+	if (((ccsr >> 9) & 1) == 0)
+		ret_val = CONFIG_MX51_HCLK_FREQ;
+	else
+		ret_val = ((32768 * 1024));
+
+	return ret_val;
+}
+
+/*
+ * get cspi clock rate.
+ */
+u32 imx_get_cspiclk(void)
+{
+	u32 ret_val = 0, pdf, pre_pdf, clk_sel;
+	u32 cscmr1 = __raw_readl(&mxc_ccm->cscmr1);
+	u32 cscdr2 = __raw_readl(&mxc_ccm->cscdr2);
+
+	pre_pdf = (cscdr2 & MXC_CCM_CSCDR2_CSPI_CLK_PRED_MASK) \
+			>> MXC_CCM_CSCDR2_CSPI_CLK_PRED_OFFSET;
+	pdf = (cscdr2 & MXC_CCM_CSCDR2_CSPI_CLK_PODF_MASK) \
+			>> MXC_CCM_CSCDR2_CSPI_CLK_PODF_OFFSET;
+	clk_sel = (cscmr1 & MXC_CCM_CSCMR1_CSPI_CLK_SEL_MASK) \
+			>> MXC_CCM_CSCMR1_CSPI_CLK_SEL_OFFSET;
+
+	switch (clk_sel) {
+	case 0:
+		ret_val = decode_pll(mxc_plls[PLL1_CLOCK],
+					CONFIG_MX51_HCLK_FREQ) /
+					((pre_pdf + 1) * (pdf + 1));
+		break;
+	case 1:
+		ret_val = decode_pll(mxc_plls[PLL2_CLOCK],
+					CONFIG_MX51_HCLK_FREQ) /
+					((pre_pdf + 1) * (pdf + 1));
+		break;
+	case 2:
+		ret_val = decode_pll(mxc_plls[PLL3_CLOCK],
+					CONFIG_MX51_HCLK_FREQ) /
+					((pre_pdf + 1) * (pdf + 1));
+		break;
+	default:
+		ret_val = get_lp_apm() / ((pre_pdf + 1) * (pdf + 1));
+		break;
+	}
+
+	return ret_val;
+}
+
+/*
+ * The API of get mxc clockes.
+ */
+unsigned int mxc_get_clock(enum mxc_clock clk)
+{
+	switch (clk) {
+	case MXC_ARM_CLK:
+		return get_mcu_main_clk();
+	case MXC_AHB_CLK:
+		break;
+	case MXC_IPG_CLK:
+		return get_ipg_clk();
+	case MXC_IPG_PERCLK:
+		return get_ipg_per_clk();
+	case MXC_UART_CLK:
+		return get_uart_clk();
+	case MXC_CSPI_CLK:
+		return imx_get_cspiclk();
+	case MXC_FEC_CLK:
+		return decode_pll(mxc_plls[PLL1_CLOCK],
+				    CONFIG_MX51_HCLK_FREQ);
+	default:
+		break;
+	}
+	return -1;
+}
+
+u32 imx_get_uartclk(void)
+{
+	return get_uart_clk();
+}
+
+
+u32 imx_get_fecclk(void)
+{
+	return mxc_get_clock(MXC_IPG_CLK);
+}
+
+/*
+ * Dump some core clockes.
+ */
+int do_mx51_showclocks(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+	u32 freq;
+
+	freq = decode_pll(mxc_plls[PLL1_CLOCK], CONFIG_MX51_HCLK_FREQ);
+	printf("mx51 pll1: %dMHz\n", freq / 1000000);
+	freq = decode_pll(mxc_plls[PLL2_CLOCK], CONFIG_MX51_HCLK_FREQ);
+	printf("mx51 pll2: %dMHz\n", freq / 1000000);
+	freq = decode_pll(mxc_plls[PLL3_CLOCK], CONFIG_MX51_HCLK_FREQ);
+	printf("mx51 pll3: %dMHz\n", freq / 1000000);
+	printf("ipg clock     : %dHz\n", mxc_get_clock(MXC_IPG_CLK));
+	printf("ipg per clock : %dHz\n", mxc_get_clock(MXC_IPG_PERCLK));
+
+	return 0;
+}
+
+/***************************************************/
+
+U_BOOT_CMD(
+	clockinfo,	CONFIG_SYS_MAXARGS,	1,	do_mx51_showclocks,
+	"display mx51 clocks\n",
+	""
+);