board: schneider: add RZN1 board support

Add support for Schneider Electric RZ/N1D and RZ/N1S boards, which
are based on the Reneasas RZ/N1 SoC devices.

The intention is to support both boards using a single defconfig, and to
handle the differences at runtime.

Signed-off-by: Ralph Siemsen <ralph.siemsen@linaro.org>
Reviewed-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
diff --git a/drivers/ram/renesas/rzn1/Makefile b/drivers/ram/renesas/rzn1/Makefile
new file mode 100644
index 0000000..357c2a5
--- /dev/null
+++ b/drivers/ram/renesas/rzn1/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0+
+
+obj-y	+= ddr_async.o
diff --git a/drivers/ram/renesas/rzn1/ddr_async.c b/drivers/ram/renesas/rzn1/ddr_async.c
new file mode 100644
index 0000000..7a81497
--- /dev/null
+++ b/drivers/ram/renesas/rzn1/ddr_async.c
@@ -0,0 +1,376 @@
+// SPDX-License-Identifier: BSD-2-Clause
+/*
+ * RZ/N1 DDR Controller initialisation
+ *
+ * The DDR Controller register values for a specific DDR device, mode and
+ * frequency are generated using a Cadence tool.
+ *
+ * Copyright (C) 2015 Renesas Electronics Europe Ltd
+ */
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <ram.h>
+#include <regmap.h>
+#include <syscon.h>
+#include <asm/io.h>
+#include <linux/delay.h>
+#include <wait_bit.h>
+#include <renesas/ddr_ctrl.h>
+
+void clk_rzn1_reset_state(struct clk *clk, int on);
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct cadence_ddr_info {
+	struct udevice *dev;
+	void __iomem *ddrc;
+	void __iomem *phy;
+	struct clk clk_ddrc;
+	struct clk hclk_ddrc;
+	struct regmap *syscon;
+	bool enable_ecc;
+	bool enable_8bit;
+	u32 ddr_size;
+
+	/* These two used only during .probe */
+	u32 *reg0;
+	u32 *reg350;
+};
+
+static inline u32 cadence_readl(void __iomem *addr, unsigned int offset)
+{
+	return readl(addr + offset);
+}
+
+static inline void cadence_writel(void __iomem *addr, unsigned int offset,
+				  u32 data)
+{
+	debug("%s: addr = 0x%p, value = 0x%08x\n", __func__, addr + offset, data);
+	writel(data, addr + offset);
+}
+
+#define ddrc_readl(off)		cadence_readl(priv->ddrc, off)
+#define ddrc_writel(val, off)	cadence_writel(priv->ddrc, off, val)
+
+#define phy_readl(off)		cadence_readl(priv->phy, off)
+#define phy_writel(val, off)	cadence_writel(priv->phy, off, val)
+
+#define RZN1_DDR3_SINGLE_BANK 3
+#define RZN1_DDR3_DUAL_BANK 32
+
+#define FUNCCTRL	0x00
+#define  FUNCCTRL_MASKSDLOFS	(0x18 << 16)
+#define  FUNCCTRL_DVDDQ_1_5V	BIT(8)
+#define  FUNCCTRL_RESET_N	BIT(0)
+#define DLLCTRL		0x04
+#define  DLLCTRL_ASDLLOCK	BIT(26)
+#define  DLLCTRL_MFSL_500MHz	(2 << 1)
+#define  DLLCTRL_MDLLSTBY	BIT(0)
+#define ZQCALCTRL	0x08
+#define  ZQCALCTRL_ZQCALEND	BIT(30)
+#define  ZQCALCTRL_ZQCALRSTB	BIT(0)
+#define ZQODTCTRL	0x0c
+#define RDCTRL		0x10
+#define RDTMG		0x14
+#define FIFOINIT	0x18
+#define  FIFOINIT_RDPTINITEXE	BIT(8)
+#define  FIFOINIT_WRPTINITEXE	BIT(0)
+#define OUTCTRL		0x1c
+#define  OUTCTRL_ADCMDOE	BIT(0)
+#define WLCTRL1		0x40
+#define  WLCTRL1_WLSTR		BIT(24)
+#define DQCALOFS1	0xe8
+
+/* DDR PHY setup */
+static void ddr_phy_init(struct cadence_ddr_info *priv, int ddr_type)
+{
+	u32 val;
+
+	/* Disable DDR Controller clock and FlexWAY connection */
+	clk_disable(&priv->hclk_ddrc);
+	clk_disable(&priv->clk_ddrc);
+
+	clk_rzn1_reset_state(&priv->hclk_ddrc, 0);
+	clk_rzn1_reset_state(&priv->clk_ddrc, 0);
+
+	/* Enable DDR Controller clock and FlexWAY connection */
+	clk_enable(&priv->clk_ddrc);
+	clk_enable(&priv->hclk_ddrc);
+
+	/* DDR PHY Soft reset assert */
+	ddrc_writel(FUNCCTRL_MASKSDLOFS | FUNCCTRL_DVDDQ_1_5V, FUNCCTRL);
+
+	clk_rzn1_reset_state(&priv->hclk_ddrc, 1);
+	clk_rzn1_reset_state(&priv->clk_ddrc, 1);
+
+	/* DDR PHY setup */
+	phy_writel(DLLCTRL_MFSL_500MHz | DLLCTRL_MDLLSTBY, DLLCTRL);
+	phy_writel(0x00000182, ZQCALCTRL);
+	if (ddr_type == RZN1_DDR3_DUAL_BANK)
+		phy_writel(0xAB330031, ZQODTCTRL);
+	else if (ddr_type == RZN1_DDR3_SINGLE_BANK)
+		phy_writel(0xAB320051, ZQODTCTRL);
+	else /* DDR2 */
+		phy_writel(0xAB330071, ZQODTCTRL);
+	phy_writel(0xB545B544, RDCTRL);
+	phy_writel(0x000000B0, RDTMG);
+	phy_writel(0x020A0806, OUTCTRL);
+	if (ddr_type == RZN1_DDR3_DUAL_BANK)
+		phy_writel(0x80005556, WLCTRL1);
+	else
+		phy_writel(0x80005C5D, WLCTRL1);
+	phy_writel(0x00000101, FIFOINIT);
+	phy_writel(0x00004545, DQCALOFS1);
+
+	/* Step 9 MDLL reset release */
+	val = phy_readl(DLLCTRL);
+	val &= ~DLLCTRL_MDLLSTBY;
+	phy_writel(val, DLLCTRL);
+
+	/* Step 12 Soft reset release */
+	val = phy_readl(FUNCCTRL);
+	val |= FUNCCTRL_RESET_N;
+	phy_writel(val, FUNCCTRL);
+
+	/* Step 13 FIFO pointer initialize */
+	phy_writel(FIFOINIT_RDPTINITEXE | FIFOINIT_WRPTINITEXE, FIFOINIT);
+
+	/* Step 14 Execute ZQ Calibration */
+	val = phy_readl(ZQCALCTRL);
+	val |= ZQCALCTRL_ZQCALRSTB;
+	phy_writel(val, ZQCALCTRL);
+
+	/* Step 15 Wait for 200us or more, or wait for DFIINITCOMPLETE to be "1" */
+	wait_for_bit_le32(priv->phy + DLLCTRL, DLLCTRL_ASDLLOCK, true, 1, false);
+	wait_for_bit_le32(priv->phy + ZQCALCTRL, ZQCALCTRL_ZQCALEND, true, 1, false);
+
+	/* Step 16 Enable Address and Command output */
+	val = phy_readl(OUTCTRL);
+	val |= OUTCTRL_ADCMDOE;
+	phy_writel(val, OUTCTRL);
+
+	/* Step 17 Wait for 200us or more(from MRESETB=0) */
+	udelay(200);
+}
+
+static void ddr_phy_enable_wl(struct cadence_ddr_info *priv)
+{
+	u32 val;
+
+	/* Step 26 (Set Write Leveling) */
+	val = phy_readl(WLCTRL1);
+	val |= WLCTRL1_WLSTR;
+	phy_writel(val, WLCTRL1);
+}
+
+#define RZN1_V_DDR_BASE               0x80000000      /* RZ/N1D only */
+
+static void rzn1_ddr3_single_bank(void *ddr_ctrl_base)
+{
+	/* CS0 */
+	cdns_ddr_set_mr1(ddr_ctrl_base, 0,
+			 MR1_ODT_IMPEDANCE_60_OHMS,
+			 MR1_DRIVE_STRENGTH_40_OHMS);
+	cdns_ddr_set_mr2(ddr_ctrl_base, 0,
+			 MR2_DYNAMIC_ODT_OFF,
+			 MR2_SELF_REFRESH_TEMP_EXT);
+
+	/* ODT_WR_MAP_CS0 = 1, ODT_RD_MAP_CS0 = 0 */
+	cdns_ddr_set_odt_map(ddr_ctrl_base, 0, 0x0100);
+}
+
+static int rzn1_dram_init(struct cadence_ddr_info *priv)
+{
+	u32 version;
+	u32 ddr_start_addr = 0;
+
+	ddr_phy_init(priv, RZN1_DDR3_SINGLE_BANK);
+
+	/*
+	 * Override DDR PHY Interface (DFI) related settings
+	 * DFI is the internal interface between the DDR controller and the DDR PHY.
+	 * These settings are specific to the board and can't be known by the settings
+	 * provided for each DDR model within the generated include.
+	 */
+	priv->reg350[351 - 350] = 0x001e0000;
+	priv->reg350[352 - 350] = 0x1e680000;
+	priv->reg350[353 - 350] = 0x02000020;
+	priv->reg350[354 - 350] = 0x02000200;
+	priv->reg350[355 - 350] = 0x00000c30;
+	priv->reg350[356 - 350] = 0x00009808;
+	priv->reg350[357 - 350] = 0x020a0706;
+	priv->reg350[372 - 350] = 0x01000000;
+
+	/*
+	 * On ES1.0 devices, the DDR start address that the DDR Controller sees
+	 * is the physical address of the DDR. However, later devices changed it
+	 * to be 0 in order to fix an issue with DDR out-of-range detection.
+	 */
+#define RZN1_SYSCTRL_REG_VERSION 412
+	regmap_read(priv->syscon, RZN1_SYSCTRL_REG_VERSION, &version);
+	if (version == 0x10)
+		ddr_start_addr = RZN1_V_DDR_BASE;
+
+	if (priv->enable_ecc)
+		priv->ddr_size = priv->ddr_size / 2;
+
+	/* DDR Controller is always in ASYNC mode */
+	cdns_ddr_ctrl_init(priv->ddrc, 1,
+			   priv->reg0, priv->reg350,
+			   ddr_start_addr, priv->ddr_size,
+			   priv->enable_ecc, priv->enable_8bit);
+
+	rzn1_ddr3_single_bank(priv->ddrc);
+	cdns_ddr_set_diff_cs_delays(priv->ddrc, 2, 7, 2, 2);
+	cdns_ddr_set_same_cs_delays(priv->ddrc, 0, 7, 0, 0);
+	cdns_ddr_set_odt_times(priv->ddrc, 5, 6, 6, 0, 4);
+	cdns_ddr_ctrl_start(priv->ddrc);
+
+	ddr_phy_enable_wl(priv);
+
+	if (priv->enable_ecc) {
+		/*
+		 * Any read before a write will trigger an ECC un-correctable error,
+		 * causing a data abort. However, this is also true for any read with a
+		 * size less than the AXI bus width. So, the only sensible solution is
+		 * to write to all of DDR now and take the hit...
+		 */
+		memset((void *)RZN1_V_DDR_BASE, 0xff, priv->ddr_size);
+	}
+
+	return 0;
+}
+
+static int cadence_ddr_get_info(struct udevice *udev, struct ram_info *info)
+{
+	info->base = 0;
+	info->size = gd->ram_size;
+
+	return 0;
+}
+
+static struct ram_ops cadence_ddr_ops = {
+	.get_info = cadence_ddr_get_info,
+};
+
+static int cadence_ddr_test(long *base, long maxsize)
+{
+	volatile long *addr = base;
+	long           cnt;
+
+	maxsize /= sizeof(long);
+
+	for (cnt = 1; cnt <= maxsize; cnt <<= 1) {
+		addr[cnt - 1] = ~cnt;
+	}
+
+	for (cnt = 1; cnt <= maxsize; cnt <<= 1) {
+		if (addr[cnt - 1] != ~cnt) {
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
+static int cadence_ddr_probe(struct udevice *dev)
+{
+	struct cadence_ddr_info *priv = dev_get_priv(dev);
+	ofnode subnode;
+	int ret;
+
+	priv->dev = dev;
+
+	priv->ddrc = dev_remap_addr_name(dev, "ddrc");
+	if (!priv->ddrc) {
+		dev_err(dev, "No reg property for Cadence DDR CTRL\n");
+		return -EINVAL;
+	}
+
+	priv->phy = dev_remap_addr_name(dev, "phy");
+	if (!priv->phy) {
+		dev_err(dev, "No reg property for Cadence DDR PHY\n");
+		return -EINVAL;
+	}
+
+	ret = clk_get_by_name(dev, "clk_ddrc", &priv->clk_ddrc);
+	if (ret) {
+		dev_err(dev, "No clock for Cadence DDR\n");
+		return ret;
+	}
+
+	ret = clk_get_by_name(dev, "hclk_ddrc", &priv->hclk_ddrc);
+	if (ret) {
+		dev_err(dev, "No HCLK for Cadence DDR\n");
+		return ret;
+	}
+
+	priv->syscon = syscon_regmap_lookup_by_phandle(dev, "syscon");
+	if (IS_ERR(priv->syscon)) {
+		dev_err(dev, "No syscon node found\n");
+		return PTR_ERR(priv->syscon);
+	}
+
+	priv->enable_ecc = dev_read_bool(dev, "enable-ecc");
+	priv->enable_8bit = dev_read_bool(dev, "enable-8bit");
+
+	priv->reg0 = malloc(88 * sizeof(u32));
+	priv->reg350 = malloc(25 * sizeof(u32));
+	if (!priv->reg0 || !priv->reg350)
+		panic("malloc failure\n");
+
+	/* There may be multiple DDR configurations to try */
+	dev_for_each_subnode(subnode, dev) {
+		ret = ofnode_read_u32(subnode, "size", &priv->ddr_size);
+		if (ret) {
+			dev_err(dev, "No size for Cadence DDR\n");
+			continue;
+		}
+
+		ret = ofnode_read_u32_array(subnode, "cadence,ctl-000", priv->reg0, 88);
+		if (ret) {
+			dev_err(dev, "No cadence,ctl-000\n");
+			continue;
+		}
+
+		ret = ofnode_read_u32_array(subnode, "cadence,ctl-350", priv->reg350, 25);
+		if (ret) {
+			dev_err(dev, "No cadence,ctl-350\n");
+			continue;
+		}
+
+		if (rzn1_dram_init(priv))
+			continue;
+
+		if (cadence_ddr_test((long *)RZN1_V_DDR_BASE, priv->ddr_size)) {
+			gd->ram_base = RZN1_V_DDR_BASE;
+			gd->ram_size = priv->ddr_size;
+			break;
+		}
+	}
+
+	if (!priv->ddr_size)
+		panic("No valid DDR to start");
+
+	free(priv->reg350);
+	free(priv->reg0);
+
+	return 0;
+}
+
+static const struct udevice_id cadence_ddr_ids[] = {
+	{ .compatible = "cadence,ddr-ctrl" },
+	{ }
+};
+
+U_BOOT_DRIVER(cadence_ddr) = {
+	.name		= "cadence_ddr",
+	.id		= UCLASS_RAM,
+	.of_match	= cadence_ddr_ids,
+	.ops		= &cadence_ddr_ops,
+	.probe		= cadence_ddr_probe,
+	.priv_auto	= sizeof(struct cadence_ddr_info),
+	.flags		= DM_FLAG_PRE_RELOC,
+};