summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/nand/lpc32xx_nand_slc.c
blob: 719a74d2f688641b3d86f65c271b4294289388aa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
/*
 * LPC32xx SLC NAND flash controller driver
 *
 * (C) Copyright 2015 Vladimir Zapolskiy <vz@mleia.com>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <nand.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/arch/clk.h>
#include <asm/arch/sys_proto.h>

struct lpc32xx_nand_slc_regs {
	u32 data;
	u32 addr;
	u32 cmd;
	u32 stop;
	u32 ctrl;
	u32 cfg;
	u32 stat;
	u32 int_stat;
	u32 ien;
	u32 isr;
	u32 icr;
	u32 tac;
	u32 tc;
	u32 ecc;
	u32 dma_data;
};

/* CFG register */
#define CFG_CE_LOW		(1 << 5)

/* CTRL register */
#define CTRL_SW_RESET		(1 << 2)

/* STAT register */
#define STAT_NAND_READY		(1 << 0)

/* INT_STAT register */
#define INT_STAT_TC		(1 << 1)
#define INT_STAT_RDY		(1 << 0)

/* TAC register bits, be aware of overflows */
#define TAC_W_RDY(n)		(max_t(uint32_t, (n), 0xF) << 28)
#define TAC_W_WIDTH(n)		(max_t(uint32_t, (n), 0xF) << 24)
#define TAC_W_HOLD(n)		(max_t(uint32_t, (n), 0xF) << 20)
#define TAC_W_SETUP(n)		(max_t(uint32_t, (n), 0xF) << 16)
#define TAC_R_RDY(n)		(max_t(uint32_t, (n), 0xF) << 12)
#define TAC_R_WIDTH(n)		(max_t(uint32_t, (n), 0xF) << 8)
#define TAC_R_HOLD(n)		(max_t(uint32_t, (n), 0xF) << 4)
#define TAC_R_SETUP(n)		(max_t(uint32_t, (n), 0xF) << 0)

static struct lpc32xx_nand_slc_regs __iomem *lpc32xx_nand_slc_regs
	= (struct lpc32xx_nand_slc_regs __iomem *)SLC_NAND_BASE;

static void lpc32xx_nand_init(void)
{
	uint32_t hclk = get_hclk_clk_rate();

	/* Reset SLC NAND controller */
	writel(CTRL_SW_RESET, &lpc32xx_nand_slc_regs->ctrl);

	/* 8-bit bus, no DMA, no ECC, ordinary CE signal */
	writel(0, &lpc32xx_nand_slc_regs->cfg);

	/* Interrupts disabled and cleared */
	writel(0, &lpc32xx_nand_slc_regs->ien);
	writel(INT_STAT_TC | INT_STAT_RDY,
	       &lpc32xx_nand_slc_regs->icr);

	/* Configure NAND flash timings */
	writel(TAC_W_RDY(CONFIG_LPC32XX_NAND_SLC_WDR_CLKS) |
	       TAC_W_WIDTH(hclk / CONFIG_LPC32XX_NAND_SLC_WWIDTH) |
	       TAC_W_HOLD(hclk / CONFIG_LPC32XX_NAND_SLC_WHOLD) |
	       TAC_W_SETUP(hclk / CONFIG_LPC32XX_NAND_SLC_WSETUP) |
	       TAC_R_RDY(CONFIG_LPC32XX_NAND_SLC_RDR_CLKS) |
	       TAC_R_WIDTH(hclk / CONFIG_LPC32XX_NAND_SLC_RWIDTH) |
	       TAC_R_HOLD(hclk / CONFIG_LPC32XX_NAND_SLC_RHOLD) |
	       TAC_R_SETUP(hclk / CONFIG_LPC32XX_NAND_SLC_RSETUP),
	       &lpc32xx_nand_slc_regs->tac);
}

static void lpc32xx_nand_cmd_ctrl(struct mtd_info *mtd,
				  int cmd, unsigned int ctrl)
{
	debug("ctrl: 0x%08x, cmd: 0x%08x\n", ctrl, cmd);

	if (ctrl & NAND_NCE)
		setbits_le32(&lpc32xx_nand_slc_regs->cfg, CFG_CE_LOW);
	else
		clrbits_le32(&lpc32xx_nand_slc_regs->cfg, CFG_CE_LOW);

	if (cmd == NAND_CMD_NONE)
		return;

	if (ctrl & NAND_CLE)
		writel(cmd & 0xFF, &lpc32xx_nand_slc_regs->cmd);
	else if (ctrl & NAND_ALE)
		writel(cmd & 0xFF, &lpc32xx_nand_slc_regs->addr);
}

static int lpc32xx_nand_dev_ready(struct mtd_info *mtd)
{
	return readl(&lpc32xx_nand_slc_regs->stat) & STAT_NAND_READY;
}

static void lpc32xx_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
	while (len-- > 0)
		*buf++ = readl(&lpc32xx_nand_slc_regs->data);
}

static uint8_t lpc32xx_read_byte(struct mtd_info *mtd)
{
	return readl(&lpc32xx_nand_slc_regs->data);
}

static void lpc32xx_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
{
	while (len-- > 0)
		writel(*buf++, &lpc32xx_nand_slc_regs->data);
}

static void lpc32xx_write_byte(struct mtd_info *mtd, uint8_t byte)
{
	writel(byte, &lpc32xx_nand_slc_regs->data);
}

/*
 * LPC32xx has only one SLC NAND controller, don't utilize
 * CONFIG_SYS_NAND_SELF_INIT to be able to reuse this function
 * both in SPL NAND and U-boot images.
 */
int board_nand_init(struct nand_chip *lpc32xx_chip)
{
	lpc32xx_chip->cmd_ctrl  = lpc32xx_nand_cmd_ctrl;
	lpc32xx_chip->dev_ready = lpc32xx_nand_dev_ready;

	/*
	 * Hardware ECC calculation is not supported by the driver,
	 * because it requires DMA support, see LPC32x0 User Manual,
	 * note after SLC_ECC register description (UM10326, p.198)
	 */
	lpc32xx_chip->ecc.mode = NAND_ECC_SOFT;

	/*
	 * The implementation of these functions is quite common, but
	 * they MUST be defined, because access to data register
	 * is strictly 32-bit aligned.
	 */
	lpc32xx_chip->read_buf   = lpc32xx_read_buf;
	lpc32xx_chip->read_byte  = lpc32xx_read_byte;
	lpc32xx_chip->write_buf  = lpc32xx_write_buf;
	lpc32xx_chip->write_byte = lpc32xx_write_byte;

	/*
	 * Use default ECC layout, but these values are predefined
	 * for both small and large page NAND flash devices.
	 */
	lpc32xx_chip->ecc.size     = 256;
	lpc32xx_chip->ecc.bytes    = 3;
	lpc32xx_chip->ecc.strength = 1;

#if defined(CONFIG_SYS_NAND_USE_FLASH_BBT)
	lpc32xx_chip->bbt_options |= NAND_BBT_USE_FLASH;
#endif

	/* Initialize NAND interface */
	lpc32xx_nand_init();

	return 0;
}
OpenPOWER on IntegriCloud