mtd: rpc: Add Renesas RPC Hyperflash driver

Add driver for the RPC block in Hyperflash mode. This driver allows
access to a CFI Hyperflash attached to the RPC block and does not
support RPC in SPI mode.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/drivers/mtd/renesas_rpc_hf.c b/drivers/mtd/renesas_rpc_hf.c
new file mode 100644
index 0000000..1ba6e35
--- /dev/null
+++ b/drivers/mtd/renesas_rpc_hf.c
@@ -0,0 +1,398 @@
+/*
+ * Renesas RCar Gen3 RPC Hyperflash driver
+ *
+ * Copyright (C) 2016 Renesas Electronics Corporation
+ * Copyright (C) 2016 Cogent Embedded, Inc.
+ * Copyright (C) 2017 Marek Vasut <marek.vasut@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <clk.h>
+#include <dm.h>
+#include <dm/of_access.h>
+#include <errno.h>
+#include <fdt_support.h>
+#include <flash.h>
+#include <mtd.h>
+#include <wait_bit.h>
+#include <mtd/cfi_flash.h>
+
+#define RPC_CMNCR		0x0000	/* R/W */
+#define RPC_CMNCR_MD		BIT(31)
+#define RPC_CMNCR_MOIIO0(val)	(((val) & 0x3) << 16)
+#define RPC_CMNCR_MOIIO1(val)	(((val) & 0x3) << 18)
+#define RPC_CMNCR_MOIIO2(val)	(((val) & 0x3) << 20)
+#define RPC_CMNCR_MOIIO3(val)	(((val) & 0x3) << 22)
+#define RPC_CMNCR_MOIIO_HIZ	(RPC_CMNCR_MOIIO0(3) | RPC_CMNCR_MOIIO1(3) | \
+				 RPC_CMNCR_MOIIO2(3) | RPC_CMNCR_MOIIO3(3))
+#define RPC_CMNCR_IO0FV(val)	(((val) & 0x3) << 8)
+#define RPC_CMNCR_IO2FV(val)	(((val) & 0x3) << 12)
+#define RPC_CMNCR_IO3FV(val)	(((val) & 0x3) << 14)
+#define RPC_CMNCR_IOFV_HIZ	(RPC_CMNCR_IO0FV(3) | RPC_CMNCR_IO2FV(3) | \
+				 RPC_CMNCR_IO3FV(3))
+#define RPC_CMNCR_BSZ(val)	(((val) & 0x3) << 0)
+
+#define RPC_SSLDR		0x0004	/* R/W */
+#define RPC_SSLDR_SPNDL(d)	(((d) & 0x7) << 16)
+#define RPC_SSLDR_SLNDL(d)	(((d) & 0x7) << 8)
+#define RPC_SSLDR_SCKDL(d)	(((d) & 0x7) << 0)
+
+#define RPC_DRCR		0x000C	/* R/W */
+#define RPC_DRCR_SSLN		BIT(24)
+#define RPC_DRCR_RBURST(v)	(((v) & 0x1F) << 16)
+#define RPC_DRCR_RCF		BIT(9)
+#define RPC_DRCR_RBE		BIT(8)
+#define RPC_DRCR_SSLE		BIT(0)
+
+#define RPC_DRCMR		0x0010	/* R/W */
+#define RPC_DRCMR_CMD(c)	(((c) & 0xFF) << 16)
+#define RPC_DRCMR_OCMD(c)	(((c) & 0xFF) << 0)
+
+#define RPC_DREAR		0x0014	/* R/W */
+#define RPC_DREAR_EAV(v)	(((v) & 0xFF) << 16)
+#define RPC_DREAR_EAC(v)	(((v) & 0x7) << 0)
+
+#define RPC_DROPR		0x0018	/* R/W */
+#define RPC_DROPR_OPD3(o)	(((o) & 0xFF) << 24)
+#define RPC_DROPR_OPD2(o)	(((o) & 0xFF) << 16)
+#define RPC_DROPR_OPD1(o)	(((o) & 0xFF) << 8)
+#define RPC_DROPR_OPD0(o)	(((o) & 0xFF) << 0)
+
+#define RPC_DRENR		0x001C	/* R/W */
+#define RPC_DRENR_CDB(o)	(u32)((((o) & 0x3) << 30))
+#define RPC_DRENR_OCDB(o)	(((o) & 0x3) << 28)
+#define RPC_DRENR_ADB(o)	(((o) & 0x3) << 24)
+#define RPC_DRENR_OPDB(o)	(((o) & 0x3) << 20)
+#define RPC_DRENR_SPIDB(o)	(((o) & 0x3) << 16)
+#define RPC_DRENR_DME		BIT(15)
+#define RPC_DRENR_CDE		BIT(14)
+#define RPC_DRENR_OCDE		BIT(12)
+#define RPC_DRENR_ADE(v)	(((v) & 0xF) << 8)
+#define RPC_DRENR_OPDE(v)	(((v) & 0xF) << 4)
+
+#define RPC_SMCR		0x0020	/* R/W */
+#define RPC_SMCR_SSLKP		BIT(8)
+#define RPC_SMCR_SPIRE		BIT(2)
+#define RPC_SMCR_SPIWE		BIT(1)
+#define RPC_SMCR_SPIE		BIT(0)
+
+#define RPC_SMCMR		0x0024	/* R/W */
+#define RPC_SMCMR_CMD(c)	(((c) & 0xFF) << 16)
+#define RPC_SMCMR_OCMD(c)	(((c) & 0xFF) << 0)
+
+#define RPC_SMADR		0x0028	/* R/W */
+#define RPC_SMOPR		0x002C	/* R/W */
+#define RPC_SMOPR_OPD0(o)	(((o) & 0xFF) << 0)
+#define RPC_SMOPR_OPD1(o)	(((o) & 0xFF) << 8)
+#define RPC_SMOPR_OPD2(o)	(((o) & 0xFF) << 16)
+#define RPC_SMOPR_OPD3(o)	(((o) & 0xFF) << 24)
+
+#define RPC_SMENR		0x0030	/* R/W */
+#define RPC_SMENR_CDB(o)	(((o) & 0x3) << 30)
+#define RPC_SMENR_OCDB(o)	(((o) & 0x3) << 28)
+#define RPC_SMENR_ADB(o)	(((o) & 0x3) << 24)
+#define RPC_SMENR_OPDB(o)	(((o) & 0x3) << 20)
+#define RPC_SMENR_SPIDB(o)	(((o) & 0x3) << 16)
+#define RPC_SMENR_DME		BIT(15)
+#define RPC_SMENR_CDE		BIT(14)
+#define RPC_SMENR_OCDE		BIT(12)
+#define RPC_SMENR_ADE(v)	(((v) & 0xF) << 8)
+#define RPC_SMENR_OPDE(v)	(((v) & 0xF) << 4)
+#define RPC_SMENR_SPIDE(v)	(((v) & 0xF) << 0)
+
+#define RPC_SMRDR0		0x0038	/* R */
+#define RPC_SMRDR1		0x003C	/* R */
+#define RPC_SMWDR0		0x0040	/* R/W */
+#define RPC_SMWDR1		0x0044	/* R/W */
+#define RPC_CMNSR		0x0048	/* R */
+#define RPC_CMNSR_SSLF		BIT(1)
+#define	RPC_CMNSR_TEND		BIT(0)
+
+#define RPC_DRDMCR		0x0058	/* R/W */
+#define RPC_DRDMCR_DMCYC(v)	(((v) & 0xF) << 0)
+
+#define RPC_DRDRENR		0x005C	/* R/W */
+#define RPC_DRDRENR_HYPE	(0x5 << 12)
+#define RPC_DRDRENR_ADDRE	BIT(8)
+#define RPC_DRDRENR_OPDRE	BIT(4)
+#define RPC_DRDRENR_DRDRE	BIT(0)
+
+#define RPC_SMDMCR		0x0060	/* R/W */
+#define RPC_SMDMCR_DMCYC(v)	(((v) & 0xF) << 0)
+
+#define RPC_SMDRENR		0x0064	/* R/W */
+#define RPC_SMDRENR_HYPE	(0x5 << 12)
+#define RPC_SMDRENR_ADDRE	BIT(8)
+#define RPC_SMDRENR_OPDRE	BIT(4)
+#define RPC_SMDRENR_SPIDRE	BIT(0)
+
+#define RPC_PHYCNT		0x007C	/* R/W */
+#define RPC_PHYCNT_CAL		BIT(31)
+#define PRC_PHYCNT_OCTA_AA	BIT(22)
+#define PRC_PHYCNT_OCTA_SA	BIT(23)
+#define PRC_PHYCNT_EXDS		BIT(21)
+#define RPC_PHYCNT_OCT		BIT(20)
+#define RPC_PHYCNT_WBUF2	BIT(4)
+#define RPC_PHYCNT_WBUF		BIT(2)
+#define RPC_PHYCNT_MEM(v)	(((v) & 0x3) << 0)
+
+#define RPC_PHYINT		0x0088	/* R/W */
+#define RPC_PHYINT_RSTEN	BIT(18)
+#define RPC_PHYINT_WPEN		BIT(17)
+#define RPC_PHYINT_INTEN	BIT(16)
+#define RPC_PHYINT_RST		BIT(2)
+#define RPC_PHYINT_WP		BIT(1)
+#define RPC_PHYINT_INT		BIT(0)
+
+#define RPC_WBUF		0x8000	/* R/W size=4/8/16/32/64Bytes */
+#define RPC_WBUF_SIZE		0x100
+
+static phys_addr_t rpc_base;
+
+enum rpc_hf_size {
+	RPC_HF_SIZE_16BIT = RPC_SMENR_SPIDE(0x8),
+	RPC_HF_SIZE_32BIT = RPC_SMENR_SPIDE(0xC),
+	RPC_HF_SIZE_64BIT = RPC_SMENR_SPIDE(0xF),
+};
+
+static int rpc_hf_wait_tend(void)
+{
+	void __iomem *reg = (void __iomem *)rpc_base + RPC_CMNSR;
+	return wait_for_bit_le32(reg, RPC_CMNSR_TEND, true, 1000, 0);
+}
+
+static int rpc_hf_mode(bool man)
+{
+	int ret;
+
+	ret = rpc_hf_wait_tend();
+	if (ret)
+		return ret;
+
+	clrsetbits_le32(rpc_base + RPC_PHYCNT,
+		 RPC_PHYCNT_WBUF | RPC_PHYCNT_WBUF2 |
+		 RPC_PHYCNT_CAL | RPC_PHYCNT_MEM(3),
+		 RPC_PHYCNT_CAL | RPC_PHYCNT_MEM(3));
+
+	clrsetbits_le32(rpc_base + RPC_CMNCR,
+		 RPC_CMNCR_MD | RPC_CMNCR_BSZ(3),
+		 RPC_CMNCR_MOIIO_HIZ | RPC_CMNCR_IOFV_HIZ |
+		 (man ? RPC_CMNCR_MD : 0) | RPC_CMNCR_BSZ(1));
+
+	if (man)
+		return 0;
+
+	writel(RPC_DRCR_RBURST(0x1F) | RPC_DRCR_RCF | RPC_DRCR_RBE,
+	       rpc_base + RPC_DRCR);
+
+	writel(RPC_DRCMR_CMD(0xA0), rpc_base + RPC_DRCMR);
+	writel(RPC_DRENR_CDB(2) | RPC_DRENR_OCDB(2) | RPC_DRENR_ADB(2) |
+	       RPC_DRENR_SPIDB(2) | RPC_DRENR_CDE | RPC_DRENR_OCDE |
+	       RPC_DRENR_ADE(4), rpc_base + RPC_DRENR);
+	writel(RPC_DRDMCR_DMCYC(0xE), rpc_base + RPC_DRDMCR);
+	writel(RPC_DRDRENR_HYPE | RPC_DRDRENR_ADDRE | RPC_DRDRENR_DRDRE,
+	       rpc_base + RPC_DRDRENR);
+
+	/* Dummy read */
+	readl(rpc_base + RPC_DRCR);
+
+	return 0;
+}
+
+static int rpc_hf_xfer(void *addr, u64 wdata, u64 *rdata,
+		       enum rpc_hf_size size, bool write)
+{
+	int ret;
+	u32 val;
+
+	ret = rpc_hf_mode(1);
+	if (ret)
+		return ret;
+
+	/* Submit HF address, SMCMR CMD[7] ~= CA Bit# 47 (R/nW) */
+	writel(write ? 0 : RPC_SMCMR_CMD(0x80), rpc_base + RPC_SMCMR);
+	writel((uintptr_t)addr >> 1, rpc_base + RPC_SMADR);
+	writel(0x0, rpc_base + RPC_SMOPR);
+
+	writel(RPC_SMDRENR_HYPE | RPC_SMDRENR_ADDRE | RPC_SMDRENR_SPIDRE,
+	       rpc_base + RPC_SMDRENR);
+
+	val = RPC_SMENR_CDB(2) | RPC_SMENR_OCDB(2) |
+	      RPC_SMENR_ADB(2) | RPC_SMENR_SPIDB(2) |
+	      RPC_SMENR_CDE | RPC_SMENR_OCDE | RPC_SMENR_ADE(4) | size;
+
+	if (write) {
+		writel(val, rpc_base + RPC_SMENR);
+
+		if (size == RPC_HF_SIZE_64BIT)
+			writeq(cpu_to_be64(wdata), rpc_base + RPC_SMWDR0);
+		else
+			writel(cpu_to_be32(wdata), rpc_base + RPC_SMWDR0);
+
+		writel(RPC_SMCR_SPIWE | RPC_SMCR_SPIE, rpc_base + RPC_SMCR);
+	} else {
+		val |= RPC_SMENR_DME;
+
+		writel(RPC_SMDMCR_DMCYC(0xE), rpc_base + RPC_SMDMCR);
+
+		writel(val, rpc_base + RPC_SMENR);
+
+		writel(RPC_SMCR_SPIRE | RPC_SMCR_SPIE, rpc_base + RPC_SMCR);
+
+		ret = rpc_hf_wait_tend();
+		if (ret)
+			return ret;
+
+		if (size == RPC_HF_SIZE_64BIT)
+			*rdata = be64_to_cpu(readq(rpc_base + RPC_SMRDR0));
+		else
+			*rdata = be32_to_cpu(readl(rpc_base + RPC_SMRDR0));
+	}
+
+	return rpc_hf_mode(0);
+}
+
+static void rpc_hf_write_cmd(void *addr, u64 wdata, enum rpc_hf_size size)
+{
+	int ret;
+
+	ret = rpc_hf_xfer(addr, wdata, NULL, size, 1);
+	if (ret)
+		printf("RPC: Write failed, ret=%i\n", ret);
+}
+
+static u64 rpc_hf_read_reg(void *addr, enum rpc_hf_size size)
+{
+	u64 rdata = 0;
+	int ret;
+
+	ret = rpc_hf_xfer(addr, 0, &rdata, size, 0);
+	if (ret)
+		printf("RPC: Read failed, ret=%i\n", ret);
+
+	return rdata;
+}
+
+void flash_write8(u8 value, void *addr)
+{
+	rpc_hf_write_cmd(addr, value, RPC_HF_SIZE_16BIT);
+}
+
+void flash_write16(u16 value, void *addr)
+{
+	rpc_hf_write_cmd(addr, value, RPC_HF_SIZE_16BIT);
+}
+
+void flash_write32(u32 value, void *addr)
+{
+	rpc_hf_write_cmd(addr, value, RPC_HF_SIZE_32BIT);
+}
+
+void flash_write64(u64 value, void *addr)
+{
+	rpc_hf_write_cmd(addr, value, RPC_HF_SIZE_64BIT);
+}
+
+u8 flash_read8(void *addr)
+{
+	return rpc_hf_read_reg(addr, RPC_HF_SIZE_16BIT);
+}
+
+u16 flash_read16(void *addr)
+{
+	return rpc_hf_read_reg(addr, RPC_HF_SIZE_16BIT);
+}
+
+u32 flash_read32(void *addr)
+{
+	return rpc_hf_read_reg(addr, RPC_HF_SIZE_32BIT);
+}
+
+u64 flash_read64(void *addr)
+{
+	return rpc_hf_read_reg(addr, RPC_HF_SIZE_64BIT);
+}
+
+static int rpc_hf_bind(struct udevice *parent)
+{
+	const void *fdt = gd->fdt_blob;
+	ofnode node;
+	int ret, off;
+
+	/*
+	 * Check if there are any SPI NOR child nodes, if so, do NOT bind
+	 * as this controller will be operated by the QSPI driver instead.
+	 */
+	dev_for_each_subnode(node, parent) {
+		off = ofnode_to_offset(node);
+
+		ret = fdt_node_check_compatible(fdt, off, "spi-flash");
+		if (!ret)
+			return -ENODEV;
+
+		ret = fdt_node_check_compatible(fdt, off, "jedec,spi-nor");
+		if (!ret)
+			return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int rpc_hf_probe(struct udevice *dev)
+{
+	void *blob = (void *)gd->fdt_blob;
+	const fdt32_t *cell;
+	int node = dev_of_offset(dev);
+	int parent, addrc, sizec, len, ret;
+	struct clk clk;
+	phys_addr_t flash_base;
+
+	parent = fdt_parent_offset(blob, node);
+	fdt_support_default_count_cells(blob, parent, &addrc, &sizec);
+	cell = fdt_getprop(blob, node, "reg", &len);
+	if (!cell)
+		return -ENOENT;
+
+	if (addrc != 2 || sizec != 2)
+		return -EINVAL;
+
+
+	ret = clk_get_by_index(dev, 0, &clk);
+	if (ret < 0) {
+		dev_err(dev, "Failed to get RPC clock\n");
+		return ret;
+	}
+
+	ret = clk_enable(&clk);
+	clk_free(&clk);
+	if (ret) {
+		dev_err(dev, "Failed to enable RPC clock\n");
+		return ret;
+	}
+
+	rpc_base = fdt_translate_address(blob, node, cell);
+	flash_base = fdt_translate_address(blob, node, cell + addrc + sizec);
+
+	flash_info[0].dev = dev;
+	flash_info[0].base = flash_base;
+	cfi_flash_num_flash_banks = 1;
+	gd->bd->bi_flashstart = flash_base;
+
+	return 0;
+}
+
+static const struct udevice_id rpc_hf_ids[] = {
+	{ .compatible = "renesas,rpc" },
+	{}
+};
+
+U_BOOT_DRIVER(rpc_hf) = {
+	.name		= "rpc_hf",
+	.id		= UCLASS_MTD,
+	.of_match	= rpc_hf_ids,
+	.bind		= rpc_hf_bind,
+	.probe		= rpc_hf_probe,
+};