2 * Copyright (C) 2015-2016 Wills Wang <wills.wang@live.com>
4 * SPDX-License-Identifier: GPL-2.0+
13 #include <asm/addrspace.h>
14 #include <asm/types.h>
15 #include <dm/pinctrl.h>
16 #include <mach/ar71xx_regs.h>
18 /* CLOCK_DIVIDER = 3 (SPI clock = 200 / 8 ~ 25 MHz) */
19 #define ATH79_SPI_CLK_DIV(x) (((x) >> 1) - 1)
20 #define ATH79_SPI_RRW_DELAY_FACTOR 12000
21 #define ATH79_SPI_MHZ (1000 * 1000)
23 struct ath79_spi_priv
{
28 static void spi_cs_activate(struct udevice
*dev
)
30 struct udevice
*bus
= dev_get_parent(dev
);
31 struct ath79_spi_priv
*priv
= dev_get_priv(bus
);
33 writel(AR71XX_SPI_FS_GPIO
, priv
->regs
+ AR71XX_SPI_REG_FS
);
34 writel(AR71XX_SPI_IOC_CS_ALL
, priv
->regs
+ AR71XX_SPI_REG_IOC
);
37 static void spi_cs_deactivate(struct udevice
*dev
)
39 struct udevice
*bus
= dev_get_parent(dev
);
40 struct ath79_spi_priv
*priv
= dev_get_priv(bus
);
42 writel(AR71XX_SPI_IOC_CS_ALL
, priv
->regs
+ AR71XX_SPI_REG_IOC
);
43 writel(0, priv
->regs
+ AR71XX_SPI_REG_FS
);
46 static int ath79_spi_claim_bus(struct udevice
*dev
)
51 static int ath79_spi_release_bus(struct udevice
*dev
)
56 static int ath79_spi_xfer(struct udevice
*dev
, unsigned int bitlen
,
57 const void *dout
, void *din
, unsigned long flags
)
59 struct udevice
*bus
= dev_get_parent(dev
);
60 struct ath79_spi_priv
*priv
= dev_get_priv(bus
);
61 struct dm_spi_slave_platdata
*slave
= dev_get_parent_platdata(dev
);
64 u8 curbyte
, curbitlen
, restbits
;
65 u32 bytes
= bitlen
/ 8;
69 if (flags
& SPI_XFER_BEGIN
)
72 restbits
= (bitlen
% 8);
76 out
= AR71XX_SPI_IOC_CS_ALL
& ~(AR71XX_SPI_IOC_CS(slave
->cs
));
83 if (restbits
&& !bytes
) {
85 curbyte
<<= 8 - restbits
;
90 for (curbyte
<<= (8 - curbitlen
); curbitlen
; curbitlen
--) {
92 out
|= AR71XX_SPI_IOC_DO
;
94 out
&= ~(AR71XX_SPI_IOC_DO
);
96 writel(out
, priv
->regs
+ AR71XX_SPI_REG_IOC
);
98 /* delay for low level */
99 if (priv
->rrw_delay
) {
100 tick
= get_ticks() + priv
->rrw_delay
;
101 while (get_ticks() < tick
)
105 writel(out
| AR71XX_SPI_IOC_CLK
,
106 priv
->regs
+ AR71XX_SPI_REG_IOC
);
108 /* delay for high level */
109 if (priv
->rrw_delay
) {
110 tick
= get_ticks() + priv
->rrw_delay
;
111 while (get_ticks() < tick
)
119 writel(out
, priv
->regs
+ AR71XX_SPI_REG_IOC
);
121 in
= readl(priv
->regs
+ AR71XX_SPI_REG_RDS
);
123 if (restbits
&& !bytes
)
124 *rx
++ = (in
<< (8 - restbits
));
130 if (flags
& SPI_XFER_END
)
131 spi_cs_deactivate(dev
);
137 static int ath79_spi_set_speed(struct udevice
*bus
, uint speed
)
139 struct ath79_spi_priv
*priv
= dev_get_priv(bus
);
144 div
= get_bus_freq(0) / speed
;
152 /* calculate delay */
154 do_div(time
, speed
/ 2);
155 val
= get_bus_freq(0) / ATH79_SPI_MHZ
;
156 val
= ATH79_SPI_RRW_DELAY_FACTOR
/ val
;
158 priv
->rrw_delay
= time
- val
+ 1;
162 writel(AR71XX_SPI_FS_GPIO
, priv
->regs
+ AR71XX_SPI_REG_FS
);
163 clrsetbits_be32(priv
->regs
+ AR71XX_SPI_REG_CTRL
,
164 AR71XX_SPI_CTRL_DIV_MASK
,
165 ATH79_SPI_CLK_DIV(div
));
166 writel(0, priv
->regs
+ AR71XX_SPI_REG_FS
);
170 static int ath79_spi_set_mode(struct udevice
*bus
, uint mode
)
175 static int ath79_spi_probe(struct udevice
*bus
)
177 struct ath79_spi_priv
*priv
= dev_get_priv(bus
);
180 addr
= devfdt_get_addr(bus
);
181 if (addr
== FDT_ADDR_T_NONE
)
184 priv
->regs
= map_physmem(addr
,
188 /* Init SPI Hardware, disable remap, set clock */
189 writel(AR71XX_SPI_FS_GPIO
, priv
->regs
+ AR71XX_SPI_REG_FS
);
190 writel(AR71XX_SPI_CTRL_RD
| ATH79_SPI_CLK_DIV(8),
191 priv
->regs
+ AR71XX_SPI_REG_CTRL
);
192 writel(0, priv
->regs
+ AR71XX_SPI_REG_FS
);
197 static int ath79_cs_info(struct udevice
*bus
, uint cs
,
198 struct spi_cs_info
*info
)
200 /* Always allow activity on CS 0/1/2 */
207 static const struct dm_spi_ops ath79_spi_ops
= {
208 .claim_bus
= ath79_spi_claim_bus
,
209 .release_bus
= ath79_spi_release_bus
,
210 .xfer
= ath79_spi_xfer
,
211 .set_speed
= ath79_spi_set_speed
,
212 .set_mode
= ath79_spi_set_mode
,
213 .cs_info
= ath79_cs_info
,
216 static const struct udevice_id ath79_spi_ids
[] = {
217 { .compatible
= "qca,ar7100-spi" },
221 U_BOOT_DRIVER(ath79_spi
) = {
224 .of_match
= ath79_spi_ids
,
225 .ops
= &ath79_spi_ops
,
226 .priv_auto_alloc_size
= sizeof(struct ath79_spi_priv
),
227 .probe
= ath79_spi_probe
,