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12#include <linux/bitops.h>
13#include <linux/module.h>
14#include <linux/pci.h>
15#include <linux/rational.h>
16
17#include <linux/dmaengine.h>
18#include <linux/dma/dw.h>
19
20#include "8250.h"
21
22#define PCI_DEVICE_ID_INTEL_QRK_UARTx 0x0936
23
24#define PCI_DEVICE_ID_INTEL_BYT_UART1 0x0f0a
25#define PCI_DEVICE_ID_INTEL_BYT_UART2 0x0f0c
26
27#define PCI_DEVICE_ID_INTEL_BSW_UART1 0x228a
28#define PCI_DEVICE_ID_INTEL_BSW_UART2 0x228c
29
30#define PCI_DEVICE_ID_INTEL_BDW_UART1 0x9ce3
31#define PCI_DEVICE_ID_INTEL_BDW_UART2 0x9ce4
32
33
34
35#define BYT_PRV_CLK 0x800
36#define BYT_PRV_CLK_EN BIT(0)
37#define BYT_PRV_CLK_M_VAL_SHIFT 1
38#define BYT_PRV_CLK_N_VAL_SHIFT 16
39#define BYT_PRV_CLK_UPDATE BIT(31)
40
41#define BYT_TX_OVF_INT 0x820
42#define BYT_TX_OVF_INT_MASK BIT(1)
43
44struct lpss8250;
45
46struct lpss8250_board {
47 unsigned long freq;
48 unsigned int base_baud;
49 int (*setup)(struct lpss8250 *, struct uart_port *p);
50 void (*exit)(struct lpss8250 *);
51};
52
53struct lpss8250 {
54 int line;
55 struct lpss8250_board *board;
56
57
58 struct uart_8250_dma dma;
59 struct dw_dma_chip dma_chip;
60 struct dw_dma_slave dma_param;
61 u8 dma_maxburst;
62};
63
64static void byt_set_termios(struct uart_port *p, struct ktermios *termios,
65 struct ktermios *old)
66{
67 unsigned int baud = tty_termios_baud_rate(termios);
68 struct lpss8250 *lpss = p->private_data;
69 unsigned long fref = lpss->board->freq, fuart = baud * 16;
70 unsigned long w = BIT(15) - 1;
71 unsigned long m, n;
72 u32 reg;
73
74
75 fuart = fuart ? fuart : 9600 * 16;
76
77
78 fuart *= rounddown_pow_of_two(fref / fuart);
79
80
81
82
83
84
85
86 rational_best_approximation(fuart, fref, w, w, &m, &n);
87 p->uartclk = fuart;
88
89
90 reg = (m << BYT_PRV_CLK_M_VAL_SHIFT) | (n << BYT_PRV_CLK_N_VAL_SHIFT);
91 writel(reg, p->membase + BYT_PRV_CLK);
92 reg |= BYT_PRV_CLK_EN | BYT_PRV_CLK_UPDATE;
93 writel(reg, p->membase + BYT_PRV_CLK);
94
95 p->status &= ~UPSTAT_AUTOCTS;
96 if (termios->c_cflag & CRTSCTS)
97 p->status |= UPSTAT_AUTOCTS;
98
99 serial8250_do_set_termios(p, termios, old);
100}
101
102static unsigned int byt_get_mctrl(struct uart_port *port)
103{
104 unsigned int ret = serial8250_do_get_mctrl(port);
105
106
107 ret |= TIOCM_CAR | TIOCM_DSR;
108
109 return ret;
110}
111
112static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port)
113{
114 struct dw_dma_slave *param = &lpss->dma_param;
115 struct uart_8250_port *up = up_to_u8250p(port);
116 struct pci_dev *pdev = to_pci_dev(port->dev);
117 unsigned int dma_devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
118 struct pci_dev *dma_dev = pci_get_slot(pdev->bus, dma_devfn);
119
120 switch (pdev->device) {
121 case PCI_DEVICE_ID_INTEL_BYT_UART1:
122 case PCI_DEVICE_ID_INTEL_BSW_UART1:
123 case PCI_DEVICE_ID_INTEL_BDW_UART1:
124 param->src_id = 3;
125 param->dst_id = 2;
126 break;
127 case PCI_DEVICE_ID_INTEL_BYT_UART2:
128 case PCI_DEVICE_ID_INTEL_BSW_UART2:
129 case PCI_DEVICE_ID_INTEL_BDW_UART2:
130 param->src_id = 5;
131 param->dst_id = 4;
132 break;
133 default:
134 return -EINVAL;
135 }
136
137 param->dma_dev = &dma_dev->dev;
138 param->m_master = 0;
139 param->p_master = 1;
140
141
142 port->fifosize = 64;
143 up->tx_loadsz = 64;
144
145 lpss->dma_maxburst = 16;
146
147 port->set_termios = byt_set_termios;
148 port->get_mctrl = byt_get_mctrl;
149
150
151 writel(BYT_TX_OVF_INT_MASK, port->membase + BYT_TX_OVF_INT);
152
153 return 0;
154}
155
156#ifdef CONFIG_SERIAL_8250_DMA
157static const struct dw_dma_platform_data qrk_serial_dma_pdata = {
158 .nr_channels = 2,
159 .is_private = true,
160 .chan_allocation_order = CHAN_ALLOCATION_ASCENDING,
161 .chan_priority = CHAN_PRIORITY_ASCENDING,
162 .block_size = 4095,
163 .nr_masters = 1,
164 .data_width = {4},
165 .multi_block = {0},
166};
167
168static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port)
169{
170 struct uart_8250_dma *dma = &lpss->dma;
171 struct dw_dma_chip *chip = &lpss->dma_chip;
172 struct dw_dma_slave *param = &lpss->dma_param;
173 struct pci_dev *pdev = to_pci_dev(port->dev);
174 int ret;
175
176 chip->dev = &pdev->dev;
177 chip->irq = pci_irq_vector(pdev, 0);
178 chip->regs = pci_ioremap_bar(pdev, 1);
179 chip->pdata = &qrk_serial_dma_pdata;
180
181
182 ret = dw_dma_probe(chip);
183 if (ret)
184 return;
185
186 pci_try_set_mwi(pdev);
187
188
189 dma->rx_dma_addr = 0xfffff000;
190 dma->tx_dma_addr = 0xfffff000;
191
192 param->dma_dev = &pdev->dev;
193 param->src_id = 0;
194 param->dst_id = 1;
195 param->hs_polarity = true;
196
197 lpss->dma_maxburst = 8;
198}
199
200static void qrk_serial_exit_dma(struct lpss8250 *lpss)
201{
202 struct dw_dma_slave *param = &lpss->dma_param;
203
204 if (!param->dma_dev)
205 return;
206 dw_dma_remove(&lpss->dma_chip);
207}
208#else
209static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port) {}
210static void qrk_serial_exit_dma(struct lpss8250 *lpss) {}
211#endif
212
213static int qrk_serial_setup(struct lpss8250 *lpss, struct uart_port *port)
214{
215 struct pci_dev *pdev = to_pci_dev(port->dev);
216 int ret;
217
218 pci_set_master(pdev);
219
220 ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
221 if (ret < 0)
222 return ret;
223
224 port->irq = pci_irq_vector(pdev, 0);
225
226 qrk_serial_setup_dma(lpss, port);
227 return 0;
228}
229
230static void qrk_serial_exit(struct lpss8250 *lpss)
231{
232 qrk_serial_exit_dma(lpss);
233}
234
235static bool lpss8250_dma_filter(struct dma_chan *chan, void *param)
236{
237 struct dw_dma_slave *dws = param;
238
239 if (dws->dma_dev != chan->device->dev)
240 return false;
241
242 chan->private = dws;
243 return true;
244}
245
246static int lpss8250_dma_setup(struct lpss8250 *lpss, struct uart_8250_port *port)
247{
248 struct uart_8250_dma *dma = &lpss->dma;
249 struct dw_dma_slave *rx_param, *tx_param;
250 struct device *dev = port->port.dev;
251
252 if (!lpss->dma_param.dma_dev)
253 return 0;
254
255 rx_param = devm_kzalloc(dev, sizeof(*rx_param), GFP_KERNEL);
256 if (!rx_param)
257 return -ENOMEM;
258
259 tx_param = devm_kzalloc(dev, sizeof(*tx_param), GFP_KERNEL);
260 if (!tx_param)
261 return -ENOMEM;
262
263 *rx_param = lpss->dma_param;
264 dma->rxconf.src_maxburst = lpss->dma_maxburst;
265
266 *tx_param = lpss->dma_param;
267 dma->txconf.dst_maxburst = lpss->dma_maxburst;
268
269 dma->fn = lpss8250_dma_filter;
270 dma->rx_param = rx_param;
271 dma->tx_param = tx_param;
272
273 port->dma = dma;
274 return 0;
275}
276
277static int lpss8250_probe(struct pci_dev *pdev, const struct pci_device_id *id)
278{
279 struct uart_8250_port uart;
280 struct lpss8250 *lpss;
281 int ret;
282
283 ret = pcim_enable_device(pdev);
284 if (ret)
285 return ret;
286
287 lpss = devm_kzalloc(&pdev->dev, sizeof(*lpss), GFP_KERNEL);
288 if (!lpss)
289 return -ENOMEM;
290
291 lpss->board = (struct lpss8250_board *)id->driver_data;
292
293 memset(&uart, 0, sizeof(struct uart_8250_port));
294
295 uart.port.dev = &pdev->dev;
296 uart.port.irq = pdev->irq;
297 uart.port.private_data = lpss;
298 uart.port.type = PORT_16550A;
299 uart.port.iotype = UPIO_MEM;
300 uart.port.regshift = 2;
301 uart.port.uartclk = lpss->board->base_baud * 16;
302 uart.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE;
303 uart.capabilities = UART_CAP_FIFO | UART_CAP_AFE;
304 uart.port.mapbase = pci_resource_start(pdev, 0);
305 uart.port.membase = pcim_iomap(pdev, 0, 0);
306 if (!uart.port.membase)
307 return -ENOMEM;
308
309 ret = lpss->board->setup(lpss, &uart.port);
310 if (ret)
311 return ret;
312
313 ret = lpss8250_dma_setup(lpss, &uart);
314 if (ret)
315 goto err_exit;
316
317 ret = serial8250_register_8250_port(&uart);
318 if (ret < 0)
319 goto err_exit;
320
321 lpss->line = ret;
322
323 pci_set_drvdata(pdev, lpss);
324 return 0;
325
326err_exit:
327 if (lpss->board->exit)
328 lpss->board->exit(lpss);
329 return ret;
330}
331
332static void lpss8250_remove(struct pci_dev *pdev)
333{
334 struct lpss8250 *lpss = pci_get_drvdata(pdev);
335
336 serial8250_unregister_port(lpss->line);
337
338 if (lpss->board->exit)
339 lpss->board->exit(lpss);
340}
341
342static const struct lpss8250_board byt_board = {
343 .freq = 100000000,
344 .base_baud = 2764800,
345 .setup = byt_serial_setup,
346};
347
348static const struct lpss8250_board qrk_board = {
349 .freq = 44236800,
350 .base_baud = 2764800,
351 .setup = qrk_serial_setup,
352 .exit = qrk_serial_exit,
353};
354
355#define LPSS_DEVICE(id, board) { PCI_VDEVICE(INTEL, id), (kernel_ulong_t)&board }
356
357static const struct pci_device_id pci_ids[] = {
358 LPSS_DEVICE(PCI_DEVICE_ID_INTEL_QRK_UARTx, qrk_board),
359 LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BYT_UART1, byt_board),
360 LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BYT_UART2, byt_board),
361 LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BSW_UART1, byt_board),
362 LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BSW_UART2, byt_board),
363 LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BDW_UART1, byt_board),
364 LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BDW_UART2, byt_board),
365 { },
366};
367MODULE_DEVICE_TABLE(pci, pci_ids);
368
369static struct pci_driver lpss8250_pci_driver = {
370 .name = "8250_lpss",
371 .id_table = pci_ids,
372 .probe = lpss8250_probe,
373 .remove = lpss8250_remove,
374};
375
376module_pci_driver(lpss8250_pci_driver);
377
378MODULE_AUTHOR("Intel Corporation");
379MODULE_LICENSE("GPL v2");
380MODULE_DESCRIPTION("Intel LPSS UART driver");
381
