mtd: rawnand: brcmnand: Add BCMBCA RAW NAND driver

The Broadcom BCA platforms are broadband access SoCs.
This is a port of the upstream Linux driver to U-Boot.
It was based on drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
from Linux v6.11.

Reviewed-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/mtd/nand/raw/Kconfig

@@ -120,6 +120,13 @@ config NAND_BRCMNAND
 	  Enable the driver for NAND flash on platforms using a Broadcom NAND
 	  controller.
 
+config NAND_BRCMNAND_BCMBCA
+	bool "Support Broadcom NAND controller on BCMBCA platforms"
+	depends on NAND_BRCMNAND && ARCH_BCMBCA
+	help
+	  Enable support for broadcom nand driver on BCA (broadband
+	  access) platforms such as BCM6846.
+
 config NAND_BRCMNAND_6368
 	bool "Support Broadcom NAND controller on bcm6368"
 	depends on NAND_BRCMNAND && ARCH_BMIPS

drivers/mtd/nand/raw/brcmnand/Makefile

@@ -6,6 +6,7 @@ obj-$(CONFIG_NAND_BRCMNAND_6753) += bcm6753_nand.o
 obj-$(CONFIG_NAND_BRCMNAND_68360) += bcm68360_nand.o
 obj-$(CONFIG_NAND_BRCMNAND_6838) += bcm6838_nand.o
 obj-$(CONFIG_NAND_BRCMNAND_6858) += bcm6858_nand.o
+obj-$(CONFIG_NAND_BRCMNAND_BCMBCA) += bcmbca_nand.o
 obj-$(CONFIG_NAND_BRCMNAND_IPROC) += iproc_nand.o
 obj-$(CONFIG_NAND_BRCMNAND) += brcmnand.o
 obj-$(CONFIG_NAND_BRCMNAND) += brcmnand_compat.o

drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c

@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <asm/io.h>
+#include <memalign.h>
+#include <nand.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <dm.h>
+#include <linux/printk.h>
+
+#include "brcmnand.h"
+
+struct bcmbca_nand_soc {
+	struct brcmnand_soc soc;
+	void __iomem *base;
+};
+
+#define BCMBCA_NAND_INT			0x00
+#define BCMBCA_NAND_STATUS_SHIFT	0
+#define BCMBCA_NAND_STATUS_MASK		(0xfff << BCMBCA_NAND_STATUS_SHIFT)
+
+#define BCMBCA_NAND_INT_EN		0x04
+#define BCMBCA_NAND_ENABLE_SHIFT	0
+#define BCMBCA_NAND_ENABLE_MASK		(0xffff << BCMBCA_NAND_ENABLE_SHIFT)
+
+enum {
+	BCMBCA_NP_READ		= BIT(0),
+	BCMBCA_BLOCK_ERASE	= BIT(1),
+	BCMBCA_COPY_BACK	= BIT(2),
+	BCMBCA_PAGE_PGM		= BIT(3),
+	BCMBCA_CTRL_READY	= BIT(4),
+	BCMBCA_DEV_RBPIN	= BIT(5),
+	BCMBCA_ECC_ERR_UNC	= BIT(6),
+	BCMBCA_ECC_ERR_CORR	= BIT(7),
+};
+
+#if defined(CONFIG_ARM64)
+#define ALIGN_REQ		8
+#else
+#define ALIGN_REQ		4
+#endif
+
+static inline bool bcmbca_nand_is_buf_aligned(void *flash_cache,  void *buffer)
+{
+	return IS_ALIGNED((uintptr_t)buffer, ALIGN_REQ) &&
+				IS_ALIGNED((uintptr_t)flash_cache, ALIGN_REQ);
+}
+
+static bool bcmbca_nand_intc_ack(struct brcmnand_soc *soc)
+{
+	struct bcmbca_nand_soc *priv =
+			container_of(soc, struct bcmbca_nand_soc, soc);
+	void __iomem *mmio = priv->base + BCMBCA_NAND_INT;
+	u32 val = brcmnand_readl(mmio);
+
+	if (val & (BCMBCA_CTRL_READY << BCMBCA_NAND_STATUS_SHIFT)) {
+		/* Ack interrupt */
+		val &= ~BCMBCA_NAND_STATUS_MASK;
+		val |= BCMBCA_CTRL_READY << BCMBCA_NAND_STATUS_SHIFT;
+		brcmnand_writel(val, mmio);
+		return true;
+	}
+
+	return false;
+}
+
+static void bcmbca_nand_intc_set(struct brcmnand_soc *soc, bool en)
+{
+	struct bcmbca_nand_soc *priv =
+			container_of(soc, struct bcmbca_nand_soc, soc);
+	void __iomem *mmio = priv->base + BCMBCA_NAND_INT_EN;
+	u32 val = brcmnand_readl(mmio);
+
+	/* Don't ack any interrupts */
+	val &= ~BCMBCA_NAND_STATUS_MASK;
+
+	if (en)
+		val |= BCMBCA_CTRL_READY << BCMBCA_NAND_ENABLE_SHIFT;
+	else
+		val &= ~(BCMBCA_CTRL_READY << BCMBCA_NAND_ENABLE_SHIFT);
+
+	brcmnand_writel(val, mmio);
+}
+
+static void bcmbca_read_data_bus(struct brcmnand_soc *soc,
+				 void __iomem *flash_cache,  u32 *buffer, int fc_words)
+{
+	/*
+	 * memcpy can do unaligned aligned access depending on source
+	 * and dest address, which is incompatible with nand cache. Fallback
+	 * to the memcpy_fromio in such case
+	 */
+	if (bcmbca_nand_is_buf_aligned((void __force *)flash_cache, buffer))
+		memcpy((void *)buffer, (void __force *)flash_cache, fc_words * 4);
+	else
+		memcpy_fromio((void *)buffer, flash_cache, fc_words * 4);
+}
+
+static int bcmbca_nand_probe(struct udevice *dev)
+{
+	struct udevice *pdev = dev;
+	struct bcmbca_nand_soc *priv = dev_get_priv(dev);
+	struct brcmnand_soc *soc;
+	struct resource res;
+
+	soc = &priv->soc;
+
+	dev_read_resource_byname(pdev, "nand-int-base", &res);
+	priv->base = devm_ioremap(dev, res.start, resource_size(&res));
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	soc->ctlrdy_ack = bcmbca_nand_intc_ack;
+	soc->ctlrdy_set_enabled = bcmbca_nand_intc_set;
+	soc->read_data_bus = bcmbca_read_data_bus;
+
+	/* Disable and ack all interrupts  */
+	brcmnand_writel(0, priv->base + BCMBCA_NAND_INT_EN);
+	brcmnand_writel(0, priv->base + BCMBCA_NAND_INT);
+
+	return brcmnand_probe(pdev, soc);
+}
+
+static const struct udevice_id bcmbca_nand_dt_ids[] = {
+	{
+		.compatible = "brcm,nand-bcm63138",
+	},
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(bcmbca_nand) = {
+	.name = "bcmbca-nand",
+	.id = UCLASS_MTD,
+	.of_match = bcmbca_nand_dt_ids,
+	.probe = bcmbca_nand_probe,
+	.priv_auto	= sizeof(struct bcmbca_nand_soc),
+};
+
+void board_nand_init(void)
+{
+	struct udevice *dev;
+	int ret;
+
+	ret = uclass_get_device_by_driver(UCLASS_MTD,
+					  DM_DRIVER_GET(bcmbca_nand), &dev);
+	if (ret && ret != -ENODEV)
+		pr_err("Failed to initialize %s. (error %d)\n", dev->name,
+		       ret);
+}