MIPS: Ingenic XBurst Jz4740 processor support

Jz4740 is a multimedia application processor targeting for mobile
devices like e-Dictionary, eBook, portable media player (PMP) and
GPS navigator.  Jz4740 is powered by Ingenic 360 MHz XBurst CPU core
(JzRISC), in which RISC/SIMD/DSP hybrid instruction set architecture
provides high integration, high performance and low power consumption.

JzRISC incorporated in Jz4740 is the advanced and power-efficient
32-bit RISC core, compatible with MIPS32, with 16K I-Cache and 16K
D-Cache, and can operate at speeds up to 400 MHz.

On-chip modules such as LCD controller, embedded audio codec, multi-
channel SAR-ADC, AC97/I2S controller and camera I/F offer a rich
suite of peripherals for multimedia application.  NAND controller
(SLC/MLC), USB (host 1.1 and device 2.0), UART, I2C, SPI, etc. are
also available.

For more info about Ingenic XBurst Jz4740:
  http://en.ingenic.cn/eng/
  http://www.linux-mips.org/wiki/Ingenic

This patch introduces XBurst CPU support in U-Boot.  It's compatible
with MIPS32, but requires a bit different cache maintenance, timer
routines, and boot mechanism using USB boot tool, so XBurst support
can go into a separate new home, cpu/xburst/.

Signed-off-by: Xiangfu Liu <xiangfu@openmobilefree.net>
Acked-by: Daniel <zpxu@ingenic.cn>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
diff --git a/arch/mips/cpu/xburst/jz4740.c b/arch/mips/cpu/xburst/jz4740.c
new file mode 100644
index 0000000..c0b9817
--- /dev/null
+++ b/arch/mips/cpu/xburst/jz4740.c
@@ -0,0 +1,248 @@
+/*
+ * Jz4740 common routines
+ * Copyright (c) 2006 Ingenic Semiconductor, <jlwei@ingenic.cn>
+ *
+ * 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 <common.h>
+#include <asm/io.h>
+#include <asm/jz4740.h>
+
+void enable_interrupts(void)
+{
+}
+
+int disable_interrupts(void)
+{
+	return 0;
+}
+
+/*
+ * PLL output clock = EXTAL * NF / (NR * NO)
+ * NF = FD + 2, NR = RD + 2
+ * NO = 1 (if OD = 0), NO = 2 (if OD = 1 or 2), NO = 4 (if OD = 3)
+ */
+void pll_init(void)
+{
+	struct jz4740_cpm *cpm = (struct jz4740_cpm *)JZ4740_CPM_BASE;
+
+	register unsigned int cfcr, plcr1;
+	int n2FR[33] = {
+		0, 0, 1, 2, 3, 0, 4, 0, 5, 0, 0, 0, 6, 0, 0, 0,
+		7, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0,
+		9
+	};
+	int div[5] = {1, 3, 3, 3, 3}; /* divisors of I:S:P:L:M */
+	int nf, pllout2;
+
+	cfcr =	CPM_CPCCR_CLKOEN |
+		CPM_CPCCR_PCS |
+		(n2FR[div[0]] << CPM_CPCCR_CDIV_BIT) |
+		(n2FR[div[1]] << CPM_CPCCR_HDIV_BIT) |
+		(n2FR[div[2]] << CPM_CPCCR_PDIV_BIT) |
+		(n2FR[div[3]] << CPM_CPCCR_MDIV_BIT) |
+		(n2FR[div[4]] << CPM_CPCCR_LDIV_BIT);
+
+	pllout2 = (cfcr & CPM_CPCCR_PCS) ?
+		CONFIG_SYS_CPU_SPEED : (CONFIG_SYS_CPU_SPEED / 2);
+
+	/* Init USB Host clock, pllout2 must be n*48MHz */
+	writel(pllout2 / 48000000 - 1, &cpm->uhccdr);
+
+	nf = CONFIG_SYS_CPU_SPEED * 2 / CONFIG_SYS_EXTAL;
+	plcr1 = ((nf - 2) << CPM_CPPCR_PLLM_BIT) | /* FD */
+		(0 << CPM_CPPCR_PLLN_BIT) |	/* RD=0, NR=2 */
+		(0 << CPM_CPPCR_PLLOD_BIT) |	/* OD=0, NO=1 */
+		(0x20 << CPM_CPPCR_PLLST_BIT) |	/* PLL stable time */
+		CPM_CPPCR_PLLEN;		/* enable PLL */
+
+	/* init PLL */
+	writel(cfcr, &cpm->cpccr);
+	writel(plcr1, &cpm->cppcr);
+}
+
+void sdram_init(void)
+{
+	struct jz4740_emc *emc = (struct jz4740_emc *)JZ4740_EMC_BASE;
+
+	register unsigned int dmcr0, dmcr, sdmode, tmp, cpu_clk, mem_clk, ns;
+
+	unsigned int cas_latency_sdmr[2] = {
+		EMC_SDMR_CAS_2,
+		EMC_SDMR_CAS_3,
+	};
+
+	unsigned int cas_latency_dmcr[2] = {
+		1 << EMC_DMCR_TCL_BIT,	/* CAS latency is 2 */
+		2 << EMC_DMCR_TCL_BIT	/* CAS latency is 3 */
+	};
+
+	int div[] = {1, 2, 3, 4, 6, 8, 12, 16, 24, 32};
+
+	cpu_clk = CONFIG_SYS_CPU_SPEED;
+	mem_clk = cpu_clk * div[__cpm_get_cdiv()] / div[__cpm_get_mdiv()];
+
+	writel(0, &emc->bcr);	/* Disable bus release */
+	writew(0, &emc->rtcsr);	/* Disable clock for counting */
+
+	/* Fault DMCR value for mode register setting*/
+#define SDRAM_ROW0	11
+#define SDRAM_COL0	8
+#define SDRAM_BANK40	0
+
+	dmcr0 = ((SDRAM_ROW0 - 11) << EMC_DMCR_RA_BIT) |
+		((SDRAM_COL0 - 8) << EMC_DMCR_CA_BIT) |
+		(SDRAM_BANK40 << EMC_DMCR_BA_BIT) |
+		(SDRAM_BW16 << EMC_DMCR_BW_BIT) |
+		EMC_DMCR_EPIN |
+		cas_latency_dmcr[((SDRAM_CASL == 3) ? 1 : 0)];
+
+	/* Basic DMCR value */
+	dmcr = ((SDRAM_ROW - 11) << EMC_DMCR_RA_BIT) |
+		((SDRAM_COL - 8) << EMC_DMCR_CA_BIT) |
+		(SDRAM_BANK4 << EMC_DMCR_BA_BIT) |
+		(SDRAM_BW16 << EMC_DMCR_BW_BIT) |
+		EMC_DMCR_EPIN |
+		cas_latency_dmcr[((SDRAM_CASL == 3) ? 1 : 0)];
+
+	/* SDRAM timimg */
+	ns = 1000000000 / mem_clk;
+	tmp = SDRAM_TRAS / ns;
+	if (tmp < 4)
+		tmp = 4;
+	if (tmp > 11)
+		tmp = 11;
+	dmcr |= (tmp - 4) << EMC_DMCR_TRAS_BIT;
+	tmp = SDRAM_RCD / ns;
+
+	if (tmp > 3)
+		tmp = 3;
+	dmcr |= tmp << EMC_DMCR_RCD_BIT;
+	tmp = SDRAM_TPC / ns;
+
+	if (tmp > 7)
+		tmp = 7;
+	dmcr |= tmp << EMC_DMCR_TPC_BIT;
+	tmp = SDRAM_TRWL / ns;
+
+	if (tmp > 3)
+		tmp = 3;
+	dmcr |= tmp << EMC_DMCR_TRWL_BIT;
+	tmp = (SDRAM_TRAS + SDRAM_TPC) / ns;
+
+	if (tmp > 14)
+		tmp = 14;
+	dmcr |= ((tmp + 1) >> 1) << EMC_DMCR_TRC_BIT;
+
+	/* SDRAM mode value */
+	sdmode = EMC_SDMR_BT_SEQ |
+		 EMC_SDMR_OM_NORMAL |
+		 EMC_SDMR_BL_4 |
+		 cas_latency_sdmr[((SDRAM_CASL == 3) ? 1 : 0)];
+
+	/* Stage 1. Precharge all banks by writing SDMR with DMCR.MRSET=0 */
+	writel(dmcr, &emc->dmcr);
+	writeb(0, JZ4740_EMC_SDMR0 | sdmode);
+
+	/* Wait for precharge, > 200us */
+	tmp = (cpu_clk / 1000000) * 1000;
+	while (tmp--)
+		;
+
+	/* Stage 2. Enable auto-refresh */
+	writel(dmcr | EMC_DMCR_RFSH, &emc->dmcr);
+
+	tmp = SDRAM_TREF / ns;
+	tmp = tmp / 64 + 1;
+	if (tmp > 0xff)
+		tmp = 0xff;
+	writew(tmp, &emc->rtcor);
+	writew(0, &emc->rtcnt);
+	/* Divisor is 64, CKO/64 */
+	writew(EMC_RTCSR_CKS_64, &emc->rtcsr);
+
+	/* Wait for number of auto-refresh cycles */
+	tmp = (cpu_clk / 1000000) * 1000;
+	while (tmp--)
+		;
+
+	/* Stage 3. Mode Register Set */
+	writel(dmcr0 | EMC_DMCR_RFSH | EMC_DMCR_MRSET, &emc->dmcr);
+	writeb(0, JZ4740_EMC_SDMR0 | sdmode);
+
+	/* Set back to basic DMCR value */
+	writel(dmcr | EMC_DMCR_RFSH | EMC_DMCR_MRSET, &emc->dmcr);
+
+	/* everything is ok now */
+}
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void calc_clocks(void)
+{
+	unsigned int pllout;
+	unsigned int div[10] = {1, 2, 3, 4, 6, 8, 12, 16, 24, 32};
+
+	pllout = __cpm_get_pllout();
+
+	gd->cpu_clk = pllout / div[__cpm_get_cdiv()];
+	gd->sys_clk = pllout / div[__cpm_get_hdiv()];
+	gd->per_clk = pllout / div[__cpm_get_pdiv()];
+	gd->mem_clk = pllout / div[__cpm_get_mdiv()];
+	gd->dev_clk = CONFIG_SYS_EXTAL;
+}
+
+void rtc_init(void)
+{
+	struct jz4740_rtc *rtc = (struct jz4740_rtc *)JZ4740_RTC_BASE;
+
+	while (!(readl(&rtc->rcr) & RTC_RCR_WRDY))
+		;
+	writel(readl(&rtc->rcr) | RTC_RCR_AE, &rtc->rcr); /* enable alarm */
+
+	while (!(readl(&rtc->rcr) & RTC_RCR_WRDY))
+		;
+	writel(0x00007fff, &rtc->rgr); /* type value */
+
+	while (!(readl(&rtc->rcr) & RTC_RCR_WRDY))
+		;
+	writel(0x0000ffe0, &rtc->hwfcr); /* Power on delay 2s */
+
+	while (!(readl(&rtc->rcr) & RTC_RCR_WRDY))
+		;
+	writel(0x00000fe0, &rtc->hrcr); /* reset delay 125ms */
+}
+
+/* U-Boot common routines */
+phys_size_t initdram(int board_type)
+{
+	struct jz4740_emc *emc = (struct jz4740_emc *)JZ4740_EMC_BASE;
+	u32 dmcr;
+	u32 rows, cols, dw, banks;
+	ulong size;
+
+	dmcr = readl(&emc->dmcr);
+	rows = 11 + ((dmcr & EMC_DMCR_RA_MASK) >> EMC_DMCR_RA_BIT);
+	cols = 8 + ((dmcr & EMC_DMCR_CA_MASK) >> EMC_DMCR_CA_BIT);
+	dw = (dmcr & EMC_DMCR_BW) ? 2 : 4;
+	banks = (dmcr & EMC_DMCR_BA) ? 4 : 2;
+
+	size = (1 << (rows + cols)) * dw * banks;
+
+	return size;
+}