sunxi: H6: Add DDR3-1333 timings

Add a routine to program the timing parameters for DDR3-1333 DRAM chips
connected to the H6 DRAM controller.

The values were gathered from doing back-calculations from a register
dump, trying to match them up with the official JEDEC DDDR3 spec.
If in doubt, the register dump values were taken for now, but the JEDEC
recommendation were added as a comment.

Many thanks to Jernej for contributing fixes!

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>

2 files changed, 145 insertions, 0 deletions

diff --git a/arch/arm/mach-sunxi/dram_timings/Makefile b/arch/arm/mach-sunxi/dram_timings/Makefile
index 0886a95968..0deb9911fd 100644
--- a/arch/arm/mach-sunxi/dram_timings/Makefile
+++ b/arch/arm/mach-sunxi/dram_timings/Makefile
@@ -2,3 +2,4 @@ obj-$(CONFIG_SUNXI_DRAM_DDR3_1333)	+= ddr3_1333.o
 obj-$(CONFIG_SUNXI_DRAM_LPDDR3_STOCK)	+= lpddr3_stock.o
 obj-$(CONFIG_SUNXI_DRAM_DDR2_V3S)	+= ddr2_v3s.o
 obj-$(CONFIG_SUNXI_DRAM_H6_LPDDR3)	+= h6_lpddr3.o
+obj-$(CONFIG_SUNXI_DRAM_H6_DDR3_1333)	+= h6_ddr3_1333.o
diff --git a/arch/arm/mach-sunxi/dram_timings/h6_ddr3_1333.c b/arch/arm/mach-sunxi/dram_timings/h6_ddr3_1333.c
new file mode 100644
index 0000000000..611eaa3024
--- /dev/null
+++ b/arch/arm/mach-sunxi/dram_timings/h6_ddr3_1333.c
@@ -0,0 +1,144 @@
+/*
+ * sun50i H6 DDR3-1333 timings, as programmed by Allwinner's boot0
+ * for some TV boxes with the H6 and DDR3 memory.
+ *
+ * The chips are probably able to be driven by a faster clock, but boot0
+ * uses a more conservative timing (as usual).
+ *
+ * (C) Copyright 2018,2019 Arm Ltd.
+ *   based on previous work by:
+ *   (C) Copyright 2017      Icenowy Zheng <icenowy@aosc.io>
+ *
+ * References used:
+ * - JEDEC DDR3 SDRAM standard:	JESD79-3F.pdf
+ * - Samsung K4B2G0446D datasheet
+ * - ZynqMP UG1087 register DDRC/PHY documentation
+ *
+ * Many thanks to Jernej Skrabec for contributing some fixes!
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/arch/dram.h>
+#include <asm/arch/cpu.h>
+
+/*
+ * Only the first four are used for DDR3(?)
+ * MR0: BL8, seq. read burst, no test, fast exit (DLL on), no DLL reset,
+ *	CAS latency (CL): 11, write recovery (WR): 12
+ * MR1: DLL enabled, output strength RZQ/6, Rtt_norm RZQ/2,
+ *	write levelling disabled, TDQS disabled, output buffer enabled
+ * MR2: manual full array self refresh, dynamic ODT off,
+ * 	CAS write latency (CWL): 8
+ */
+static u32 mr_ddr3[7] = {
+	0x00001c70, 0x00000040, 0x00000018, 0x00000000,
+	0x00000000, 0x00000400, 0x00000848,
+};
+
+/* TODO: flexible timing */
+void mctl_set_timing_params(struct dram_para *para)
+{
+	struct sunxi_mctl_ctl_reg * const mctl_ctl =
+			(struct sunxi_mctl_ctl_reg *)SUNXI_DRAM_CTL0_BASE;
+	struct sunxi_mctl_phy_reg * const mctl_phy =
+			(struct sunxi_mctl_phy_reg *)SUNXI_DRAM_PHY0_BASE;
+	int i;
+
+	u8 tccd		= 2;			/* JEDEC: 4nCK */
+	u8 tfaw		= ns_to_t(50);		/* JEDEC: 30 ns w/ 1K pages */
+	u8 trrd		= max(ns_to_t(6), 4);	/* JEDEC: max(6 ns, 4nCK) */
+	u8 trcd		= ns_to_t(15);		/* JEDEC: 13.5 ns */
+	u8 trc		= ns_to_t(53);		/* JEDEC: 49.5 ns */
+	u8 txp		= max(ns_to_t(6), 3);	/* JEDEC: max(6 ns, 3nCK) */
+	u8 twtr		= max(ns_to_t(8), 2);	/* JEDEC: max(7.5 ns, 4nCK) */
+	u8 trtp		= max(ns_to_t(8), 2);	/* JEDEC: max(7.5 ns, 4nCK) */
+	u8 twr		= ns_to_t(15);		/* JEDEC: 15 ns */
+	u8 trp		= ns_to_t(15);		/* JEDEC: >= 13.75 ns */
+	u8 tras		= ns_to_t(38);		/* JEDEC >= 36 ns, <= 9*trefi */
+	u8 twtr_sa	= 2;			/* ? */
+	u8 tcksrea	= 4;			/* ? */
+	u16 trefi	= ns_to_t(7800) / 32;	/* JEDEC: 7.8us@Tcase <= 85C */
+	u16 trfc	= ns_to_t(350);		/* JEDEC: 160 ns for 2Gb */
+	u16 txsr	= 4;			/* ? */
+
+	u8 tmrw		= 0;			/* ? */
+	u8 tmrd		= 4;			/* JEDEC: 4nCK */
+	u8 tmod		= max(ns_to_t(15), 12);	/* JEDEC: max(15 ns, 12nCK) */
+	u8 tcke		= max(ns_to_t(6), 3);	/* JEDEC: max(5.625 ns, 3nCK) */
+	u8 tcksrx	= max(ns_to_t(10), 5);	/* JEDEC: max(10 ns, 5nCK) */
+	u8 tcksre	= max(ns_to_t(10), 5);	/* JEDEC: max(10 ns, 5nCK) */
+	u8 tckesr	= tcke + 1;		/* JEDEC: tCKE(min) + 1nCK */
+	u8 trasmax	= 24;			/* JEDEC: tREFI * 9 */
+	u8 txs		= ns_to_t(360) / 32;	/* JEDEC: max(5nCK,tRFC+10ns) */
+	u8 txsdll	= 4;			/* JEDEC: 512 nCK */
+	u8 txsabort	= 4;			/* ? */
+	u8 txsfast	= 4;			/* ? */
+	u8 tcl		= 6;			/* JEDEC: CL / 2 => 6 */
+	u8 tcwl		= 4;			/* JEDEC: 8 */
+	u8 t_rdata_en	= 7;			/* ? */
+
+	u32 tdinit0	= (500 * CONFIG_DRAM_CLK) + 1;	/* 500us */
+	u32 tdinit1	= (360 * CONFIG_DRAM_CLK) / 1000 + 1;
+	u32 tdinit2	= (200 * CONFIG_DRAM_CLK) + 1;
+	u32 tdinit3	= (1 * CONFIG_DRAM_CLK) + 1;	/* 1us */
+
+	u8 twtp		= tcwl + 2 + twr;	/* (WL + BL / 2 + tWR) / 2 */
+	u8 twr2rd	= tcwl + 2 + twtr;	/* (WL + BL / 2 + tWTR) / 2 */
+	u8 trd2wr	= 5;			/* (RL + BL / 2 + 2 - WL) / 2 */
+
+	if (tcl + 1 >= trtp + trp)
+		trtp = tcl + 2 - trp;
+
+	/* set mode registers */
+	for (i = 0; i < ARRAY_SIZE(mr_ddr3); i++)
+		writel(mr_ddr3[i], &mctl_phy->mr[i]);
+
+	/* set DRAM timing */
+	writel((twtp << 24) | (tfaw << 16) | (trasmax << 8) | tras,
+	       &mctl_ctl->dramtmg[0]);
+	writel((txp << 16) | (trtp << 8) | trc, &mctl_ctl->dramtmg[1]);
+	writel((tcwl << 24) | (tcl << 16) | (trd2wr << 8) | twr2rd,
+	       &mctl_ctl->dramtmg[2]);
+	writel((tmrw << 20) | (tmrd << 12) | tmod, &mctl_ctl->dramtmg[3]);
+	writel((trcd << 24) | (tccd << 16) | (trrd << 8) | trp,
+	       &mctl_ctl->dramtmg[4]);
+	writel((tcksrx << 24) | (tcksre << 16) | (tckesr << 8) | tcke,
+	       &mctl_ctl->dramtmg[5]);
+	/* Value suggested by ZynqMP manual and used by libdram */
+	writel((txp + 2) | 0x02020000, &mctl_ctl->dramtmg[6]);
+	writel((txsfast << 24) | (txsabort << 16) | (txsdll << 8) | txs,
+	       &mctl_ctl->dramtmg[8]);
+	writel(txsr, &mctl_ctl->dramtmg[14]);
+
+	clrsetbits_le32(&mctl_ctl->init[0], (3 << 30), (1 << 30));
+	writel(0, &mctl_ctl->dfimisc);
+	clrsetbits_le32(&mctl_ctl->rankctl, 0xff0, 0x660);
+
+	/*
+	 * Set timing registers of the PHY.
+	 * Note: the PHY is clocked 2x from the DRAM frequency.
+	 */
+	writel((trrd << 25) | (tras << 17) | (trp << 9) | (trtp << 1),
+	       &mctl_phy->dtpr[0]);
+	writel((tfaw << 17) | 0x28000400 | (tmrd << 1), &mctl_phy->dtpr[1]);
+	writel(((txs << 6) - 1) | (tcke << 17), &mctl_phy->dtpr[2]);
+	writel(((txsdll << 22) - (0x1 << 16)) | twtr_sa | (tcksrea << 8),
+	       &mctl_phy->dtpr[3]);
+	writel((txp << 1) | (trfc << 17) | 0x800, &mctl_phy->dtpr[4]);
+	writel((trc << 17) | (trcd << 9) | (twtr << 1), &mctl_phy->dtpr[5]);
+	writel(0x0505, &mctl_phy->dtpr[6]);
+
+	/* Configure DFI timing */
+	writel(tcl | 0x2000200 | (t_rdata_en << 16) | 0x808000,
+	       &mctl_ctl->dfitmg0);
+	writel(0x040201, &mctl_ctl->dfitmg1);
+
+	/* Configure PHY timing. Zynq uses different registers. */
+	writel(tdinit0 | (tdinit1 << 20), &mctl_phy->ptr[3]);
+	writel(tdinit2 | (tdinit3 << 18), &mctl_phy->ptr[4]);
+
+	/* set refresh timing */
+	writel((trefi << 16) | trfc, &mctl_ctl->rfshtmg);
+}