bcmbca_nand.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright © 2015 Broadcom Corporation
  4 */
  5
  6#include <linux/device.h>
  7#include <linux/io.h>
  8#include <linux/ioport.h>
  9#include <linux/module.h>
 10#include <linux/of.h>
 11#include <linux/of_address.h>
 12#include <linux/platform_device.h>
 13#include <linux/slab.h>
 14
 15#include "brcmnand.h"
 16
 17struct bcmbca_nand_soc {
 18	struct brcmnand_soc soc;
 19	void __iomem *base;
 20};
 21
 22#define BCMBCA_NAND_INT_STATUS		0x00
 23#define BCMBCA_NAND_INT_EN			0x04
 24
 25enum {
 26	BCMBCA_CTLRDY		= BIT(4),
 27};
 28
 29#if defined(CONFIG_ARM64)
 30#define ALIGN_REQ		8
 31#else
 32#define ALIGN_REQ		4
 33#endif
 34
 35static inline bool bcmbca_nand_is_buf_aligned(void *flash_cache,  void *buffer)
 36{
 37	return IS_ALIGNED((uintptr_t)buffer, ALIGN_REQ) &&
 38				IS_ALIGNED((uintptr_t)flash_cache, ALIGN_REQ);
 39}
 40
 41static bool bcmbca_nand_intc_ack(struct brcmnand_soc *soc)
 42{
 43	struct bcmbca_nand_soc *priv =
 44			container_of(soc, struct bcmbca_nand_soc, soc);
 45	void __iomem *mmio = priv->base + BCMBCA_NAND_INT_STATUS;
 46	u32 val = brcmnand_readl(mmio);
 47
 48	if (val & BCMBCA_CTLRDY) {
 49		brcmnand_writel(val & ~BCMBCA_CTLRDY, mmio);
 50		return true;
 51	}
 52
 53	return false;
 54}
 55
 56static void bcmbca_nand_intc_set(struct brcmnand_soc *soc, bool en)
 57{
 58	struct bcmbca_nand_soc *priv =
 59			container_of(soc, struct bcmbca_nand_soc, soc);
 60	void __iomem *mmio = priv->base + BCMBCA_NAND_INT_EN;
 61	u32 val = brcmnand_readl(mmio);
 62
 63	if (en)
 64		val |= BCMBCA_CTLRDY;
 65	else
 66		val &= ~BCMBCA_CTLRDY;
 67
 68	brcmnand_writel(val, mmio);
 69}
 70
 71static void bcmbca_read_data_bus(struct brcmnand_soc *soc,
 72				 void __iomem *flash_cache,  u32 *buffer, int fc_words)
 73{
 74	/*
 75	 * memcpy can do unaligned aligned access depending on source
 76	 * and dest address, which is incompatible with nand cache. Fallback
 77	 * to the memcpy_fromio in such case
 78	 */
 79	if (bcmbca_nand_is_buf_aligned((void __force *)flash_cache, buffer))
 80		memcpy((void *)buffer, (void __force *)flash_cache, fc_words * 4);
 81	else
 82		memcpy_fromio((void *)buffer, flash_cache, fc_words * 4);
 83}
 84
 85static int bcmbca_nand_probe(struct platform_device *pdev)
 86{
 87	struct device *dev = &pdev->dev;
 88	struct bcmbca_nand_soc *priv;
 89	struct brcmnand_soc *soc;
 90
 91	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 92	if (!priv)
 93		return -ENOMEM;
 94	soc = &priv->soc;
 95
 96	priv->base = devm_platform_ioremap_resource_byname(pdev, "nand-int-base");
 97	if (IS_ERR(priv->base))
 98		return PTR_ERR(priv->base);
 99
100	soc->ctlrdy_ack = bcmbca_nand_intc_ack;
101	soc->ctlrdy_set_enabled = bcmbca_nand_intc_set;
102	soc->read_data_bus = bcmbca_read_data_bus;
103
104	return brcmnand_probe(pdev, soc);
105}
106
107static const struct of_device_id bcmbca_nand_of_match[] = {
108	{ .compatible = "brcm,nand-bcm63138" },
109	{},
110};
111MODULE_DEVICE_TABLE(of, bcmbca_nand_of_match);
112
113static struct platform_driver bcmbca_nand_driver = {
114	.probe			= bcmbca_nand_probe,
115	.remove			= brcmnand_remove,
116	.driver = {
117		.name		= "bcmbca_nand",
118		.pm		= &brcmnand_pm_ops,
119		.of_match_table	= bcmbca_nand_of_match,
120	}
121};
122module_platform_driver(bcmbca_nand_driver);
123
124MODULE_LICENSE("GPL v2");
125MODULE_AUTHOR("Brian Norris");
126MODULE_DESCRIPTION("NAND driver for BCMBCA");