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7#include <common.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 <mach/ar71xx_regs.h>
17
18#define AR933X_UART_DATA_REG 0x00
19#define AR933X_UART_CS_REG 0x04
20#define AR933X_UART_CLK_REG 0x08
21
22#define AR933X_UART_DATA_TX_RX_MASK 0xff
23#define AR933X_UART_DATA_RX_CSR BIT(8)
24#define AR933X_UART_DATA_TX_CSR BIT(9)
25#define AR933X_UART_CS_IF_MODE_S 2
26#define AR933X_UART_CS_IF_MODE_M 0x3
27#define AR933X_UART_CS_IF_MODE_DTE 1
28#define AR933X_UART_CS_IF_MODE_DCE 2
29#define AR933X_UART_CS_TX_RDY_ORIDE BIT(7)
30#define AR933X_UART_CS_RX_RDY_ORIDE BIT(8)
31#define AR933X_UART_CLK_STEP_M 0xffff
32#define AR933X_UART_CLK_SCALE_M 0xfff
33#define AR933X_UART_CLK_SCALE_S 16
34#define AR933X_UART_CLK_STEP_S 0
35
36struct ar933x_serial_priv {
37 void __iomem *regs;
38};
39
40
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42
43
44static u32 ar933x_serial_get_baud(u32 clk, u32 scale, u32 step)
45{
46 u64 t;
47 u32 div;
48
49 div = (2 << 16) * (scale + 1);
50 t = clk;
51 t *= step;
52 t += (div / 2);
53 do_div(t, div);
54
55 return t;
56}
57
58static void ar933x_serial_get_scale_step(u32 clk, u32 baud,
59 u32 *scale, u32 *step)
60{
61 u32 tscale, baudrate;
62 long min_diff;
63
64 *scale = 0;
65 *step = 0;
66
67 min_diff = baud;
68 for (tscale = 0; tscale < AR933X_UART_CLK_SCALE_M; tscale++) {
69 u64 tstep;
70 int diff;
71
72 tstep = baud * (tscale + 1);
73 tstep *= (2 << 16);
74 do_div(tstep, clk);
75
76 if (tstep > AR933X_UART_CLK_STEP_M)
77 break;
78
79 baudrate = ar933x_serial_get_baud(clk, tscale, tstep);
80 diff = abs(baudrate - baud);
81 if (diff < min_diff) {
82 min_diff = diff;
83 *scale = tscale;
84 *step = tstep;
85 }
86 }
87}
88
89static int ar933x_serial_setbrg(struct udevice *dev, int baudrate)
90{
91 struct ar933x_serial_priv *priv = dev_get_priv(dev);
92 u32 val, scale, step;
93
94 val = get_serial_clock();
95 ar933x_serial_get_scale_step(val, baudrate, &scale, &step);
96
97 val = (scale & AR933X_UART_CLK_SCALE_M)
98 << AR933X_UART_CLK_SCALE_S;
99 val |= (step & AR933X_UART_CLK_STEP_M)
100 << AR933X_UART_CLK_STEP_S;
101 writel(val, priv->regs + AR933X_UART_CLK_REG);
102
103 return 0;
104}
105
106static int ar933x_serial_putc(struct udevice *dev, const char c)
107{
108 struct ar933x_serial_priv *priv = dev_get_priv(dev);
109 u32 data;
110
111 data = readl(priv->regs + AR933X_UART_DATA_REG);
112 if (!(data & AR933X_UART_DATA_TX_CSR))
113 return -EAGAIN;
114
115 data = (u32)c | AR933X_UART_DATA_TX_CSR;
116 writel(data, priv->regs + AR933X_UART_DATA_REG);
117
118 return 0;
119}
120
121static int ar933x_serial_getc(struct udevice *dev)
122{
123 struct ar933x_serial_priv *priv = dev_get_priv(dev);
124 u32 data;
125
126 data = readl(priv->regs + AR933X_UART_DATA_REG);
127 if (!(data & AR933X_UART_DATA_RX_CSR))
128 return -EAGAIN;
129
130 writel(AR933X_UART_DATA_RX_CSR, priv->regs + AR933X_UART_DATA_REG);
131 return data & AR933X_UART_DATA_TX_RX_MASK;
132}
133
134static int ar933x_serial_pending(struct udevice *dev, bool input)
135{
136 struct ar933x_serial_priv *priv = dev_get_priv(dev);
137 u32 data;
138
139 data = readl(priv->regs + AR933X_UART_DATA_REG);
140 if (input)
141 return (data & AR933X_UART_DATA_RX_CSR) ? 1 : 0;
142 else
143 return (data & AR933X_UART_DATA_TX_CSR) ? 0 : 1;
144}
145
146static int ar933x_serial_probe(struct udevice *dev)
147{
148 struct ar933x_serial_priv *priv = dev_get_priv(dev);
149 fdt_addr_t addr;
150 u32 val;
151
152 addr = devfdt_get_addr(dev);
153 if (addr == FDT_ADDR_T_NONE)
154 return -EINVAL;
155
156 priv->regs = map_physmem(addr, AR933X_UART_SIZE,
157 MAP_NOCACHE);
158
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167
168 val = (AR933X_UART_CS_IF_MODE_DCE << AR933X_UART_CS_IF_MODE_S) |
169 AR933X_UART_CS_TX_RDY_ORIDE | AR933X_UART_CS_RX_RDY_ORIDE;
170 writel(val, priv->regs + AR933X_UART_CS_REG);
171 return 0;
172}
173
174static const struct dm_serial_ops ar933x_serial_ops = {
175 .putc = ar933x_serial_putc,
176 .pending = ar933x_serial_pending,
177 .getc = ar933x_serial_getc,
178 .setbrg = ar933x_serial_setbrg,
179};
180
181static const struct udevice_id ar933x_serial_ids[] = {
182 { .compatible = "qca,ar9330-uart" },
183 { }
184};
185
186U_BOOT_DRIVER(serial_ar933x) = {
187 .name = "serial_ar933x",
188 .id = UCLASS_SERIAL,
189 .of_match = ar933x_serial_ids,
190 .priv_auto_alloc_size = sizeof(struct ar933x_serial_priv),
191 .probe = ar933x_serial_probe,
192 .ops = &ar933x_serial_ops,
193 .flags = DM_FLAG_PRE_RELOC,
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
