sunxi: add support for the DDR2 in V3s SoC

Allwinner V3s SoC features a co-packaged DDR2 DRAM chip, which needs its
timing param.

Add support for it.

Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com>

arch/arm/mach-sunxi/Kconfig

@@ -220,6 +220,9 @@ if SUNXI_DRAM_DW
 config SUNXI_DRAM_DDR3
 	bool
 
+config SUNXI_DRAM_DDR2
+	bool
+
 choice
 	prompt "DRAM Type and Timing"
 	default SUNXI_DRAM_DDR3_1333
@@ -231,6 +234,13 @@ config SUNXI_DRAM_DDR3_1333
 	This option is the original only supported memory type, which suits
 	many H3/H5/A64 boards available now.
 
+config SUNXI_DRAM_DDR2_V3S
+	bool "DDR2 found in V3s chip"
+	select SUNXI_DRAM_DDR2
+	---help---
+	This option is only for the DDR2 memory chip which is co-packaged in
+	Allwinner V3s SoC.
+
 endchoice
 endif
 

arch/arm/mach-sunxi/dram_sunxi_dw.c

@@ -340,6 +340,8 @@ static void mctl_set_cr(uint16_t socid, struct dram_para *para)
 	writel(MCTL_CR_BL8 | MCTL_CR_INTERLEAVED |
 #if defined CONFIG_SUNXI_DRAM_DDR3
 	       MCTL_CR_DDR3 | MCTL_CR_2T |
+#elif defined CONFIG_SUNXI_DRAM_DDR2
+	       MCTL_CR_DDR2 | MCTL_CR_2T |
 #else
 #error Unsupported DRAM type!
 #endif

arch/arm/mach-sunxi/dram_timings/Makefile

@@ -1 +1,2 @@
 obj-$(CONFIG_SUNXI_DRAM_DDR3_1333)	+= ddr3_1333.o
+obj-$(CONFIG_SUNXI_DRAM_DDR2_V3S)	+= ddr2_v3s.o

arch/arm/mach-sunxi/dram_timings/ddr2_v3s.c

@@ -0,0 +1,84 @@
+#include <common.h>
+#include <asm/arch/dram.h>
+#include <asm/arch/cpu.h>
+
+void mctl_set_timing_params(uint16_t socid, struct dram_para *para)
+{
+	struct sunxi_mctl_ctl_reg * const mctl_ctl =
+			(struct sunxi_mctl_ctl_reg *)SUNXI_DRAM_CTL0_BASE;
+
+	u8 tccd		= 1;
+	u8 tfaw		= ns_to_t(50);
+	u8 trrd		= max(ns_to_t(10), 2);
+	u8 trcd		= ns_to_t(20);
+	u8 trc		= ns_to_t(65);
+	u8 txp		= 2;
+	u8 twtr		= max(ns_to_t(8), 2);
+	u8 trtp		= max(ns_to_t(8), 2);
+	u8 twr		= max(ns_to_t(15), 3);
+	u8 trp		= ns_to_t(15);
+	u8 tras		= ns_to_t(45);
+	u16 trefi	= ns_to_t(7800) / 32;
+	u16 trfc	= ns_to_t(328);
+
+	u8 tmrw		= 0;
+	u8 tmrd		= 2;
+	u8 tmod		= 12;
+	u8 tcke		= 3;
+	u8 tcksrx	= 5;
+	u8 tcksre	= 5;
+	u8 tckesr	= 4;
+	u8 trasmax	= 27;
+
+	u8 tcl		= 3; /* CL 6 */
+	u8 tcwl		= 3; /* CWL 6 */
+	u8 t_rdata_en	= 1;
+	u8 wr_latency	= 1;
+
+	u32 tdinit0	= (400 * CONFIG_DRAM_CLK) + 1;		/* 400us */
+	u32 tdinit1	= (500 * CONFIG_DRAM_CLK) / 1000 + 1;	/* 500ns */
+	u32 tdinit2	= (200 * CONFIG_DRAM_CLK) + 1;		/* 200us */
+	u32 tdinit3	= (1 * CONFIG_DRAM_CLK) + 1;		/* 1us */
+
+	u8 twtp		= tcwl + 2 + twr;	/* WL + BL / 2 + tWR */
+	u8 twr2rd	= tcwl + 2 + twtr;	/* WL + BL / 2 + tWTR */
+	u8 trd2wr	= tcl + 2 + 1 - tcwl;	/* RL + BL / 2 + 2 - WL */
+
+	/* set mode register */
+	writel(0x263, &mctl_ctl->mr[0]);
+	writel(0x4, &mctl_ctl->mr[1]);
+	writel(0x0, &mctl_ctl->mr[2]);
+	writel(0x0, &mctl_ctl->mr[3]);
+
+	/* set DRAM timing */
+	writel(DRAMTMG0_TWTP(twtp) | DRAMTMG0_TFAW(tfaw) |
+	       DRAMTMG0_TRAS_MAX(trasmax) | DRAMTMG0_TRAS(tras),
+	       &mctl_ctl->dramtmg[0]);
+	writel(DRAMTMG1_TXP(txp) | DRAMTMG1_TRTP(trtp) | DRAMTMG1_TRC(trc),
+	       &mctl_ctl->dramtmg[1]);
+	writel(DRAMTMG2_TCWL(tcwl) | DRAMTMG2_TCL(tcl) |
+	       DRAMTMG2_TRD2WR(trd2wr) | DRAMTMG2_TWR2RD(twr2rd),
+	       &mctl_ctl->dramtmg[2]);
+	writel(DRAMTMG3_TMRW(tmrw) | DRAMTMG3_TMRD(tmrd) | DRAMTMG3_TMOD(tmod),
+	       &mctl_ctl->dramtmg[3]);
+	writel(DRAMTMG4_TRCD(trcd) | DRAMTMG4_TCCD(tccd) | DRAMTMG4_TRRD(trrd) |
+	       DRAMTMG4_TRP(trp), &mctl_ctl->dramtmg[4]);
+	writel(DRAMTMG5_TCKSRX(tcksrx) | DRAMTMG5_TCKSRE(tcksre) |
+	       DRAMTMG5_TCKESR(tckesr) | DRAMTMG5_TCKE(tcke),
+	       &mctl_ctl->dramtmg[5]);
+
+	/* set two rank timing */
+	clrsetbits_le32(&mctl_ctl->dramtmg[8], (0xff << 8) | (0xff << 0),
+			(0x66 << 8) | (0x10 << 0));
+
+	/* set PHY interface timing, write latency and read latency configure */
+	writel((0x2 << 24) | (t_rdata_en << 16) | (0x1 << 8) |
+	       (wr_latency << 0), &mctl_ctl->pitmg[0]);
+
+	/* set PHY timing, PTR0-2 use default */
+	writel(PTR3_TDINIT0(tdinit0) | PTR3_TDINIT1(tdinit1), &mctl_ctl->ptr[3]);
+	writel(PTR4_TDINIT2(tdinit2) | PTR4_TDINIT3(tdinit3), &mctl_ctl->ptr[4]);
+
+	/* set refresh timing */
+	writel(RFSHTMG_TREFI(trefi) | RFSHTMG_TRFC(trfc), &mctl_ctl->rfshtmg);
+}