xref: /linux/drivers/mtd/nand/raw/brcmnand/iproc_nand.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 
17 struct iproc_nand_soc {
18 	struct brcmnand_soc soc;
19 
20 	void __iomem *idm_base;
21 	void __iomem *ext_base;
22 	spinlock_t idm_lock;
23 };
24 
25 #define IPROC_NAND_CTLR_READY_OFFSET       0x10
26 #define IPROC_NAND_CTLR_READY              BIT(0)
27 
28 #define IPROC_NAND_IO_CTRL_OFFSET          0x00
29 #define IPROC_NAND_APB_LE_MODE             BIT(24)
30 #define IPROC_NAND_INT_CTRL_READ_ENABLE    BIT(6)
31 
32 static bool iproc_nand_intc_ack(struct brcmnand_soc *soc)
33 {
34 	struct iproc_nand_soc *priv =
35 			container_of(soc, struct iproc_nand_soc, soc);
36 	void __iomem *mmio = priv->ext_base + IPROC_NAND_CTLR_READY_OFFSET;
37 	u32 val = brcmnand_readl(mmio);
38 
39 	if (val & IPROC_NAND_CTLR_READY) {
40 		brcmnand_writel(IPROC_NAND_CTLR_READY, mmio);
41 		return true;
42 	}
43 
44 	return false;
45 }
46 
47 static void iproc_nand_intc_set(struct brcmnand_soc *soc, bool en)
48 {
49 	struct iproc_nand_soc *priv =
50 			container_of(soc, struct iproc_nand_soc, soc);
51 	void __iomem *mmio = priv->idm_base + IPROC_NAND_IO_CTRL_OFFSET;
52 	u32 val;
53 	unsigned long flags;
54 
55 	spin_lock_irqsave(&priv->idm_lock, flags);
56 
57 	val = brcmnand_readl(mmio);
58 
59 	if (en)
60 		val |= IPROC_NAND_INT_CTRL_READ_ENABLE;
61 	else
62 		val &= ~IPROC_NAND_INT_CTRL_READ_ENABLE;
63 
64 	brcmnand_writel(val, mmio);
65 
66 	spin_unlock_irqrestore(&priv->idm_lock, flags);
67 }
68 
69 static void iproc_nand_apb_access(struct brcmnand_soc *soc, bool prepare,
70 				  bool is_param)
71 {
72 	struct iproc_nand_soc *priv =
73 			container_of(soc, struct iproc_nand_soc, soc);
74 	void __iomem *mmio = priv->idm_base + IPROC_NAND_IO_CTRL_OFFSET;
75 	u32 val;
76 	unsigned long flags;
77 
78 	spin_lock_irqsave(&priv->idm_lock, flags);
79 
80 	val = brcmnand_readl(mmio);
81 
82 	/*
83 	 * In the case of BE or when dealing with NAND data, alway configure
84 	 * the APB bus to LE mode before accessing the FIFO and back to BE mode
85 	 * after the access is done
86 	 */
87 	if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) || !is_param) {
88 		if (prepare)
89 			val |= IPROC_NAND_APB_LE_MODE;
90 		else
91 			val &= ~IPROC_NAND_APB_LE_MODE;
92 	} else { /* when in LE accessing the parameter page, keep APB in BE */
93 		val &= ~IPROC_NAND_APB_LE_MODE;
94 	}
95 
96 	brcmnand_writel(val, mmio);
97 
98 	spin_unlock_irqrestore(&priv->idm_lock, flags);
99 }
100 
101 static int iproc_nand_probe(struct platform_device *pdev)
102 {
103 	struct device *dev = &pdev->dev;
104 	struct iproc_nand_soc *priv;
105 	struct brcmnand_soc *soc;
106 
107 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
108 	if (!priv)
109 		return -ENOMEM;
110 	soc = &priv->soc;
111 
112 	spin_lock_init(&priv->idm_lock);
113 
114 	priv->idm_base = devm_platform_ioremap_resource_byname(pdev, "iproc-idm");
115 	if (IS_ERR(priv->idm_base))
116 		return PTR_ERR(priv->idm_base);
117 
118 	priv->ext_base = devm_platform_ioremap_resource_byname(pdev, "iproc-ext");
119 	if (IS_ERR(priv->ext_base))
120 		return PTR_ERR(priv->ext_base);
121 
122 	soc->ctlrdy_ack = iproc_nand_intc_ack;
123 	soc->ctlrdy_set_enabled = iproc_nand_intc_set;
124 	soc->prepare_data_bus = iproc_nand_apb_access;
125 
126 	return brcmnand_probe(pdev, soc);
127 }
128 
129 static const struct of_device_id iproc_nand_of_match[] = {
130 	{ .compatible = "brcm,nand-iproc" },
131 	{},
132 };
133 MODULE_DEVICE_TABLE(of, iproc_nand_of_match);
134 
135 static struct platform_driver iproc_nand_driver = {
136 	.probe			= iproc_nand_probe,
137 	.remove			= brcmnand_remove,
138 	.driver = {
139 		.name		= "iproc_nand",
140 		.pm		= &brcmnand_pm_ops,
141 		.of_match_table	= iproc_nand_of_match,
142 	}
143 };
144 module_platform_driver(iproc_nand_driver);
145 
146 MODULE_LICENSE("GPL v2");
147 MODULE_AUTHOR("Brian Norris");
148 MODULE_AUTHOR("Ray Jui");
149 MODULE_DESCRIPTION("NAND driver for Broadcom IPROC-based SoCs");
150