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6#include <common.h>
7#include <clock_legacy.h>
8#include <dm.h>
9#include <div64.h>
10#include <errno.h>
11#include <serial.h>
12#include <asm/io.h>
13#include <asm/addrspace.h>
14#include <asm/types.h>
15#include <dm/pinctrl.h>
16#include <linux/bitops.h>
17#include <mach/ar71xx_regs.h>
18
19#define AR933X_UART_DATA_REG 0x00
20#define AR933X_UART_CS_REG 0x04
21#define AR933X_UART_CLK_REG 0x08
22
23#define AR933X_UART_DATA_TX_RX_MASK 0xff
24#define AR933X_UART_DATA_RX_CSR BIT(8)
25#define AR933X_UART_DATA_TX_CSR BIT(9)
26#define AR933X_UART_CS_IF_MODE_S 2
27#define AR933X_UART_CS_IF_MODE_M 0x3
28#define AR933X_UART_CS_IF_MODE_DTE 1
29#define AR933X_UART_CS_IF_MODE_DCE 2
30#define AR933X_UART_CS_TX_RDY_ORIDE BIT(7)
31#define AR933X_UART_CS_RX_RDY_ORIDE BIT(8)
32#define AR933X_UART_CLK_STEP_M 0xffff
33#define AR933X_UART_CLK_SCALE_M 0xfff
34#define AR933X_UART_CLK_SCALE_S 16
35#define AR933X_UART_CLK_STEP_S 0
36
37struct ar933x_serial_priv {
38 void __iomem *regs;
39};
40
41
42
43
44
45static u32 ar933x_serial_get_baud(u32 clk, u32 scale, u32 step)
46{
47 u64 t;
48 u32 div;
49
50 div = (2 << 16) * (scale + 1);
51 t = clk;
52 t *= step;
53 t += (div / 2);
54 do_div(t, div);
55
56 return t;
57}
58
59static void ar933x_serial_get_scale_step(u32 clk, u32 baud,
60 u32 *scale, u32 *step)
61{
62 u32 tscale, baudrate;
63 long min_diff;
64
65 *scale = 0;
66 *step = 0;
67
68 min_diff = baud;
69 for (tscale = 0; tscale < AR933X_UART_CLK_SCALE_M; tscale++) {
70 u64 tstep;
71 int diff;
72
73 tstep = baud * (tscale + 1);
74 tstep *= (2 << 16);
75 do_div(tstep, clk);
76
77 if (tstep > AR933X_UART_CLK_STEP_M)
78 break;
79
80 baudrate = ar933x_serial_get_baud(clk, tscale, tstep);
81 diff = abs(baudrate - baud);
82 if (diff < min_diff) {
83 min_diff = diff;
84 *scale = tscale;
85 *step = tstep;
86 }
87 }
88}
89
90static int ar933x_serial_setbrg(struct udevice *dev, int baudrate)
91{
92 struct ar933x_serial_priv *priv = dev_get_priv(dev);
93 u32 val, scale, step;
94
95 val = get_serial_clock();
96 ar933x_serial_get_scale_step(val, baudrate, &scale, &step);
97
98 val = (scale & AR933X_UART_CLK_SCALE_M)
99 << AR933X_UART_CLK_SCALE_S;
100 val |= (step & AR933X_UART_CLK_STEP_M)
101 << AR933X_UART_CLK_STEP_S;
102 writel(val, priv->regs + AR933X_UART_CLK_REG);
103
104 return 0;
105}
106
107static int ar933x_serial_putc(struct udevice *dev, const char c)
108{
109 struct ar933x_serial_priv *priv = dev_get_priv(dev);
110 u32 data;
111
112 data = readl(priv->regs + AR933X_UART_DATA_REG);
113 if (!(data & AR933X_UART_DATA_TX_CSR))
114 return -EAGAIN;
115
116 data = (u32)c | AR933X_UART_DATA_TX_CSR;
117 writel(data, priv->regs + AR933X_UART_DATA_REG);
118
119 return 0;
120}
121
122static int ar933x_serial_getc(struct udevice *dev)
123{
124 struct ar933x_serial_priv *priv = dev_get_priv(dev);
125 u32 data;
126
127 data = readl(priv->regs + AR933X_UART_DATA_REG);
128 if (!(data & AR933X_UART_DATA_RX_CSR))
129 return -EAGAIN;
130
131 writel(AR933X_UART_DATA_RX_CSR, priv->regs + AR933X_UART_DATA_REG);
132 return data & AR933X_UART_DATA_TX_RX_MASK;
133}
134
135static int ar933x_serial_pending(struct udevice *dev, bool input)
136{
137 struct ar933x_serial_priv *priv = dev_get_priv(dev);
138 u32 data;
139
140 data = readl(priv->regs + AR933X_UART_DATA_REG);
141 if (input)
142 return (data & AR933X_UART_DATA_RX_CSR) ? 1 : 0;
143 else
144 return (data & AR933X_UART_DATA_TX_CSR) ? 0 : 1;
145}
146
147static int ar933x_serial_probe(struct udevice *dev)
148{
149 struct ar933x_serial_priv *priv = dev_get_priv(dev);
150 fdt_addr_t addr;
151 u32 val;
152
153 addr = dev_read_addr(dev);
154 if (addr == FDT_ADDR_T_NONE)
155 return -EINVAL;
156
157 priv->regs = map_physmem(addr, AR933X_UART_SIZE,
158 MAP_NOCACHE);
159
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167
168
169 val = (AR933X_UART_CS_IF_MODE_DCE << AR933X_UART_CS_IF_MODE_S) |
170 AR933X_UART_CS_TX_RDY_ORIDE | AR933X_UART_CS_RX_RDY_ORIDE;
171 writel(val, priv->regs + AR933X_UART_CS_REG);
172 return 0;
173}
174
175static const struct dm_serial_ops ar933x_serial_ops = {
176 .putc = ar933x_serial_putc,
177 .pending = ar933x_serial_pending,
178 .getc = ar933x_serial_getc,
179 .setbrg = ar933x_serial_setbrg,
180};
181
182static const struct udevice_id ar933x_serial_ids[] = {
183 { .compatible = "qca,ar9330-uart" },
184 { }
185};
186
187U_BOOT_DRIVER(serial_ar933x) = {
188 .name = "serial_ar933x",
189 .id = UCLASS_SERIAL,
190 .of_match = ar933x_serial_ids,
191 .priv_auto = sizeof(struct ar933x_serial_priv),
192 .probe = ar933x_serial_probe,
193 .ops = &ar933x_serial_ops,
194};
195
196#ifdef CONFIG_DEBUG_UART_AR933X
197
198#include <debug_uart.h>
199
200static inline void _debug_uart_init(void)
201{
202 void __iomem *regs = (void *)CONFIG_DEBUG_UART_BASE;
203 u32 val, scale, step;
204
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213
214 val = (AR933X_UART_CS_IF_MODE_DCE << AR933X_UART_CS_IF_MODE_S) |
215 AR933X_UART_CS_TX_RDY_ORIDE | AR933X_UART_CS_RX_RDY_ORIDE;
216 writel(val, regs + AR933X_UART_CS_REG);
217
218 ar933x_serial_get_scale_step(CONFIG_DEBUG_UART_CLOCK,
219 CONFIG_BAUDRATE, &scale, &step);
220
221 val = (scale & AR933X_UART_CLK_SCALE_M)
222 << AR933X_UART_CLK_SCALE_S;
223 val |= (step & AR933X_UART_CLK_STEP_M)
224 << AR933X_UART_CLK_STEP_S;
225 writel(val, regs + AR933X_UART_CLK_REG);
226}
227
228static inline void _debug_uart_putc(int c)
229{
230 void __iomem *regs = (void *)CONFIG_DEBUG_UART_BASE;
231 u32 data;
232
233 do {
234 data = readl(regs + AR933X_UART_DATA_REG);
235 } while (!(data & AR933X_UART_DATA_TX_CSR));
236
237 data = (u32)c | AR933X_UART_DATA_TX_CSR;
238 writel(data, regs + AR933X_UART_DATA_REG);
239}
240
241DEBUG_UART_FUNCS
242
243#endif
244
