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v3.5.6
 
  1#include <linux/console.h>
  2#include <linux/kernel.h>
  3#include <linux/init.h>
  4#include <linux/string.h>
  5#include <linux/screen_info.h>
  6#include <linux/usb/ch9.h>
  7#include <linux/pci_regs.h>
  8#include <linux/pci_ids.h>
  9#include <linux/errno.h>
 
 10#include <asm/io.h>
 11#include <asm/processor.h>
 12#include <asm/fcntl.h>
 13#include <asm/setup.h>
 14#include <xen/hvc-console.h>
 15#include <asm/pci-direct.h>
 16#include <asm/fixmap.h>
 17#include <asm/mrst.h>
 18#include <asm/pgtable.h>
 19#include <linux/usb/ehci_def.h>
 
 
 20
 21/* Simple VGA output */
 22#define VGABASE		(__ISA_IO_base + 0xb8000)
 23
 24static int max_ypos = 25, max_xpos = 80;
 25static int current_ypos = 25, current_xpos;
 26
 27static void early_vga_write(struct console *con, const char *str, unsigned n)
 28{
 29	char c;
 30	int  i, k, j;
 31
 32	while ((c = *str++) != '\0' && n-- > 0) {
 33		if (current_ypos >= max_ypos) {
 34			/* scroll 1 line up */
 35			for (k = 1, j = 0; k < max_ypos; k++, j++) {
 36				for (i = 0; i < max_xpos; i++) {
 37					writew(readw(VGABASE+2*(max_xpos*k+i)),
 38					       VGABASE + 2*(max_xpos*j + i));
 39				}
 40			}
 41			for (i = 0; i < max_xpos; i++)
 42				writew(0x720, VGABASE + 2*(max_xpos*j + i));
 43			current_ypos = max_ypos-1;
 44		}
 45#ifdef CONFIG_KGDB_KDB
 46		if (c == '\b') {
 47			if (current_xpos > 0)
 48				current_xpos--;
 49		} else if (c == '\r') {
 50			current_xpos = 0;
 51		} else
 52#endif
 53		if (c == '\n') {
 54			current_xpos = 0;
 55			current_ypos++;
 56		} else if (c != '\r')  {
 57			writew(((0x7 << 8) | (unsigned short) c),
 58			       VGABASE + 2*(max_xpos*current_ypos +
 59						current_xpos++));
 60			if (current_xpos >= max_xpos) {
 61				current_xpos = 0;
 62				current_ypos++;
 63			}
 64		}
 65	}
 66}
 67
 68static struct console early_vga_console = {
 69	.name =		"earlyvga",
 70	.write =	early_vga_write,
 71	.flags =	CON_PRINTBUFFER,
 72	.index =	-1,
 73};
 74
 75/* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
 76
 77static int early_serial_base = 0x3f8;  /* ttyS0 */
 78
 79#define XMTRDY          0x20
 80
 81#define DLAB		0x80
 82
 83#define TXR             0       /*  Transmit register (WRITE) */
 84#define RXR             0       /*  Receive register  (READ)  */
 85#define IER             1       /*  Interrupt Enable          */
 86#define IIR             2       /*  Interrupt ID              */
 87#define FCR             2       /*  FIFO control              */
 88#define LCR             3       /*  Line control              */
 89#define MCR             4       /*  Modem control             */
 90#define LSR             5       /*  Line Status               */
 91#define MSR             6       /*  Modem Status              */
 92#define DLL             0       /*  Divisor Latch Low         */
 93#define DLH             1       /*  Divisor latch High        */
 94
 
 
 
 
 
 
 
 
 
 
 
 
 
 95static int early_serial_putc(unsigned char ch)
 96{
 97	unsigned timeout = 0xffff;
 98
 99	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
100		cpu_relax();
101	outb(ch, early_serial_base + TXR);
102	return timeout ? 0 : -1;
103}
104
105static void early_serial_write(struct console *con, const char *s, unsigned n)
106{
107	while (*s && n-- > 0) {
108		if (*s == '\n')
109			early_serial_putc('\r');
110		early_serial_putc(*s);
111		s++;
112	}
113}
114
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
115#define DEFAULT_BAUD 9600
116
117static __init void early_serial_init(char *s)
118{
119	unsigned char c;
120	unsigned divisor;
121	unsigned baud = DEFAULT_BAUD;
122	char *e;
123
124	if (*s == ',')
125		++s;
126
127	if (*s) {
128		unsigned port;
129		if (!strncmp(s, "0x", 2)) {
130			early_serial_base = simple_strtoul(s, &e, 16);
131		} else {
132			static const int __initconst bases[] = { 0x3f8, 0x2f8 };
133
134			if (!strncmp(s, "ttyS", 4))
135				s += 4;
136			port = simple_strtoul(s, &e, 10);
137			if (port > 1 || s == e)
138				port = 0;
139			early_serial_base = bases[port];
140		}
141		s += strcspn(s, ",");
142		if (*s == ',')
143			s++;
144	}
145
146	outb(0x3, early_serial_base + LCR);	/* 8n1 */
147	outb(0, early_serial_base + IER);	/* no interrupt */
148	outb(0, early_serial_base + FCR);	/* no fifo */
149	outb(0x3, early_serial_base + MCR);	/* DTR + RTS */
150
151	if (*s) {
152		baud = simple_strtoul(s, &e, 0);
 
153		if (baud == 0 || s == e)
154			baud = DEFAULT_BAUD;
155	}
156
 
157	divisor = 115200 / baud;
158	c = inb(early_serial_base + LCR);
159	outb(c | DLAB, early_serial_base + LCR);
160	outb(divisor & 0xff, early_serial_base + DLL);
161	outb((divisor >> 8) & 0xff, early_serial_base + DLH);
162	outb(c & ~DLAB, early_serial_base + LCR);
 
 
163}
164
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
165static struct console early_serial_console = {
166	.name =		"earlyser",
167	.write =	early_serial_write,
168	.flags =	CON_PRINTBUFFER,
169	.index =	-1,
170};
171
172/* Direct interface for emergencies */
173static struct console *early_console = &early_vga_console;
174static int __initdata early_console_initialized;
175
176asmlinkage void early_printk(const char *fmt, ...)
177{
178	char buf[512];
179	int n;
180	va_list ap;
181
182	va_start(ap, fmt);
183	n = vscnprintf(buf, sizeof(buf), fmt, ap);
184	early_console->write(early_console, buf, n);
185	va_end(ap);
186}
187
188static inline void early_console_register(struct console *con, int keep_early)
189{
190	if (early_console->index != -1) {
191		printk(KERN_CRIT "ERROR: earlyprintk= %s already used\n",
192		       con->name);
193		return;
194	}
195	early_console = con;
196	if (keep_early)
197		early_console->flags &= ~CON_BOOT;
198	else
199		early_console->flags |= CON_BOOT;
200	register_console(early_console);
201}
202
203static int __init setup_early_printk(char *buf)
204{
205	int keep;
206
207	if (!buf)
208		return 0;
209
210	if (early_console_initialized)
211		return 0;
212	early_console_initialized = 1;
213
214	keep = (strstr(buf, "keep") != NULL);
215
216	while (*buf != '\0') {
217		if (!strncmp(buf, "serial", 6)) {
218			buf += 6;
219			early_serial_init(buf);
220			early_console_register(&early_serial_console, keep);
221			if (!strncmp(buf, ",ttyS", 5))
222				buf += 5;
223		}
224		if (!strncmp(buf, "ttyS", 4)) {
225			early_serial_init(buf + 4);
226			early_console_register(&early_serial_console, keep);
227		}
 
 
 
 
 
 
 
228		if (!strncmp(buf, "vga", 3) &&
229		    boot_params.screen_info.orig_video_isVGA == 1) {
230			max_xpos = boot_params.screen_info.orig_video_cols;
231			max_ypos = boot_params.screen_info.orig_video_lines;
232			current_ypos = boot_params.screen_info.orig_y;
233			early_console_register(&early_vga_console, keep);
234		}
235#ifdef CONFIG_EARLY_PRINTK_DBGP
236		if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4))
237			early_console_register(&early_dbgp_console, keep);
238#endif
239#ifdef CONFIG_HVC_XEN
240		if (!strncmp(buf, "xen", 3))
241			early_console_register(&xenboot_console, keep);
242#endif
243#ifdef CONFIG_EARLY_PRINTK_INTEL_MID
244		if (!strncmp(buf, "mrst", 4)) {
245			mrst_early_console_init();
246			early_console_register(&early_mrst_console, keep);
247		}
248
249		if (!strncmp(buf, "hsu", 3)) {
250			hsu_early_console_init(buf + 3);
251			early_console_register(&early_hsu_console, keep);
252		}
253#endif
 
254		buf++;
255	}
256	return 0;
257}
258
259early_param("earlyprintk", setup_early_printk);
v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/console.h>
  3#include <linux/kernel.h>
  4#include <linux/init.h>
  5#include <linux/string.h>
  6#include <linux/screen_info.h>
  7#include <linux/usb/ch9.h>
  8#include <linux/pci_regs.h>
  9#include <linux/pci_ids.h>
 10#include <linux/errno.h>
 11#include <linux/pgtable.h>
 12#include <asm/io.h>
 13#include <asm/processor.h>
 14#include <asm/fcntl.h>
 15#include <asm/setup.h>
 16#include <xen/hvc-console.h>
 17#include <asm/pci-direct.h>
 18#include <asm/fixmap.h>
 
 
 19#include <linux/usb/ehci_def.h>
 20#include <linux/usb/xhci-dbgp.h>
 21#include <asm/pci_x86.h>
 22
 23/* Simple VGA output */
 24#define VGABASE		(__ISA_IO_base + 0xb8000)
 25
 26static int max_ypos = 25, max_xpos = 80;
 27static int current_ypos = 25, current_xpos;
 28
 29static void early_vga_write(struct console *con, const char *str, unsigned n)
 30{
 31	char c;
 32	int  i, k, j;
 33
 34	while ((c = *str++) != '\0' && n-- > 0) {
 35		if (current_ypos >= max_ypos) {
 36			/* scroll 1 line up */
 37			for (k = 1, j = 0; k < max_ypos; k++, j++) {
 38				for (i = 0; i < max_xpos; i++) {
 39					writew(readw(VGABASE+2*(max_xpos*k+i)),
 40					       VGABASE + 2*(max_xpos*j + i));
 41				}
 42			}
 43			for (i = 0; i < max_xpos; i++)
 44				writew(0x720, VGABASE + 2*(max_xpos*j + i));
 45			current_ypos = max_ypos-1;
 46		}
 47#ifdef CONFIG_KGDB_KDB
 48		if (c == '\b') {
 49			if (current_xpos > 0)
 50				current_xpos--;
 51		} else if (c == '\r') {
 52			current_xpos = 0;
 53		} else
 54#endif
 55		if (c == '\n') {
 56			current_xpos = 0;
 57			current_ypos++;
 58		} else if (c != '\r')  {
 59			writew(((0x7 << 8) | (unsigned short) c),
 60			       VGABASE + 2*(max_xpos*current_ypos +
 61						current_xpos++));
 62			if (current_xpos >= max_xpos) {
 63				current_xpos = 0;
 64				current_ypos++;
 65			}
 66		}
 67	}
 68}
 69
 70static struct console early_vga_console = {
 71	.name =		"earlyvga",
 72	.write =	early_vga_write,
 73	.flags =	CON_PRINTBUFFER,
 74	.index =	-1,
 75};
 76
 77/* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
 78
 79static unsigned long early_serial_base = 0x3f8;  /* ttyS0 */
 80
 81#define XMTRDY          0x20
 82
 83#define DLAB		0x80
 84
 85#define TXR             0       /*  Transmit register (WRITE) */
 86#define RXR             0       /*  Receive register  (READ)  */
 87#define IER             1       /*  Interrupt Enable          */
 88#define IIR             2       /*  Interrupt ID              */
 89#define FCR             2       /*  FIFO control              */
 90#define LCR             3       /*  Line control              */
 91#define MCR             4       /*  Modem control             */
 92#define LSR             5       /*  Line Status               */
 93#define MSR             6       /*  Modem Status              */
 94#define DLL             0       /*  Divisor Latch Low         */
 95#define DLH             1       /*  Divisor latch High        */
 96
 97static unsigned int io_serial_in(unsigned long addr, int offset)
 98{
 99	return inb(addr + offset);
100}
101
102static void io_serial_out(unsigned long addr, int offset, int value)
103{
104	outb(value, addr + offset);
105}
106
107static unsigned int (*serial_in)(unsigned long addr, int offset) = io_serial_in;
108static void (*serial_out)(unsigned long addr, int offset, int value) = io_serial_out;
109
110static int early_serial_putc(unsigned char ch)
111{
112	unsigned timeout = 0xffff;
113
114	while ((serial_in(early_serial_base, LSR) & XMTRDY) == 0 && --timeout)
115		cpu_relax();
116	serial_out(early_serial_base, TXR, ch);
117	return timeout ? 0 : -1;
118}
119
120static void early_serial_write(struct console *con, const char *s, unsigned n)
121{
122	while (*s && n-- > 0) {
123		if (*s == '\n')
124			early_serial_putc('\r');
125		early_serial_putc(*s);
126		s++;
127	}
128}
129
130static __init void early_serial_hw_init(unsigned divisor)
131{
132	unsigned char c;
133
134	serial_out(early_serial_base, LCR, 0x3);	/* 8n1 */
135	serial_out(early_serial_base, IER, 0);	/* no interrupt */
136	serial_out(early_serial_base, FCR, 0);	/* no fifo */
137	serial_out(early_serial_base, MCR, 0x3);	/* DTR + RTS */
138
139	c = serial_in(early_serial_base, LCR);
140	serial_out(early_serial_base, LCR, c | DLAB);
141	serial_out(early_serial_base, DLL, divisor & 0xff);
142	serial_out(early_serial_base, DLH, (divisor >> 8) & 0xff);
143	serial_out(early_serial_base, LCR, c & ~DLAB);
144}
145
146#define DEFAULT_BAUD 9600
147
148static __init void early_serial_init(char *s)
149{
 
150	unsigned divisor;
151	unsigned long baud = DEFAULT_BAUD;
152	char *e;
153
154	if (*s == ',')
155		++s;
156
157	if (*s) {
158		unsigned port;
159		if (!strncmp(s, "0x", 2)) {
160			early_serial_base = simple_strtoul(s, &e, 16);
161		} else {
162			static const int __initconst bases[] = { 0x3f8, 0x2f8 };
163
164			if (!strncmp(s, "ttyS", 4))
165				s += 4;
166			port = simple_strtoul(s, &e, 10);
167			if (port > 1 || s == e)
168				port = 0;
169			early_serial_base = bases[port];
170		}
171		s += strcspn(s, ",");
172		if (*s == ',')
173			s++;
174	}
175
 
 
 
 
 
176	if (*s) {
177		baud = simple_strtoull(s, &e, 0);
178
179		if (baud == 0 || s == e)
180			baud = DEFAULT_BAUD;
181	}
182
183	/* Convert from baud to divisor value */
184	divisor = 115200 / baud;
185
186	/* These will always be IO based ports */
187	serial_in = io_serial_in;
188	serial_out = io_serial_out;
189
190	/* Set up the HW */
191	early_serial_hw_init(divisor);
192}
193
194#ifdef CONFIG_PCI
195static void mem32_serial_out(unsigned long addr, int offset, int value)
196{
197	u32 __iomem *vaddr = (u32 __iomem *)addr;
198	/* shift implied by pointer type */
199	writel(value, vaddr + offset);
200}
201
202static unsigned int mem32_serial_in(unsigned long addr, int offset)
203{
204	u32 __iomem *vaddr = (u32 __iomem *)addr;
205	/* shift implied by pointer type */
206	return readl(vaddr + offset);
207}
208
209/*
210 * early_pci_serial_init()
211 *
212 * This function is invoked when the early_printk param starts with "pciserial"
213 * The rest of the param should be "[force],B:D.F,baud", where B, D & F describe
214 * the location of a PCI device that must be a UART device. "force" is optional
215 * and overrides the use of an UART device with a wrong PCI class code.
216 */
217static __init void early_pci_serial_init(char *s)
218{
219	unsigned divisor;
220	unsigned long baud = DEFAULT_BAUD;
221	u8 bus, slot, func;
222	u32 classcode, bar0;
223	u16 cmdreg;
224	char *e;
225	int force = 0;
226
227	if (*s == ',')
228		++s;
229
230	if (*s == 0)
231		return;
232
233	/* Force the use of an UART device with wrong class code */
234	if (!strncmp(s, "force,", 6)) {
235		force = 1;
236		s += 6;
237	}
238
239	/*
240	 * Part the param to get the BDF values
241	 */
242	bus = (u8)simple_strtoul(s, &e, 16);
243	s = e;
244	if (*s != ':')
245		return;
246	++s;
247	slot = (u8)simple_strtoul(s, &e, 16);
248	s = e;
249	if (*s != '.')
250		return;
251	++s;
252	func = (u8)simple_strtoul(s, &e, 16);
253	s = e;
254
255	/* A baud might be following */
256	if (*s == ',')
257		s++;
258
259	/*
260	 * Find the device from the BDF
261	 */
262	cmdreg = read_pci_config(bus, slot, func, PCI_COMMAND);
263	classcode = read_pci_config(bus, slot, func, PCI_CLASS_REVISION);
264	bar0 = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
265
266	/*
267	 * Verify it is a 16550-UART type device
268	 */
269	if (((classcode >> 16 != PCI_CLASS_COMMUNICATION_MODEM) &&
270	     (classcode >> 16 != PCI_CLASS_COMMUNICATION_SERIAL)) ||
271	    (((classcode >> 8) & 0xff) != PCI_SERIAL_16550_COMPATIBLE)) {
272		if (!force)
273			return;
274	}
275
276	/*
277	 * Determine if it is IO or memory mapped
278	 */
279	if ((bar0 & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
280		/* it is IO mapped */
281		serial_in = io_serial_in;
282		serial_out = io_serial_out;
283		early_serial_base = bar0 & PCI_BASE_ADDRESS_IO_MASK;
284		write_pci_config(bus, slot, func, PCI_COMMAND,
285				 cmdreg|PCI_COMMAND_IO);
286	} else {
287		/* It is memory mapped - assume 32-bit alignment */
288		serial_in = mem32_serial_in;
289		serial_out = mem32_serial_out;
290		/* WARNING! assuming the address is always in the first 4G */
291		early_serial_base =
292			(unsigned long)early_ioremap(bar0 & PCI_BASE_ADDRESS_MEM_MASK, 0x10);
293		write_pci_config(bus, slot, func, PCI_COMMAND,
294				 cmdreg|PCI_COMMAND_MEMORY);
295	}
296
297	/*
298	 * Initialize the hardware
299	 */
300	if (*s) {
301		if (strcmp(s, "nocfg") == 0)
302			/* Sometimes, we want to leave the UART alone
303			 * and assume the BIOS has set it up correctly.
304			 * "nocfg" tells us this is the case, and we
305			 * should do no more setup.
306			 */
307			return;
308		if (kstrtoul(s, 0, &baud) < 0 || baud == 0)
309			baud = DEFAULT_BAUD;
310	}
311
312	/* Convert from baud to divisor value */
313	divisor = 115200 / baud;
314
315	/* Set up the HW */
316	early_serial_hw_init(divisor);
317}
318#endif
319
320static struct console early_serial_console = {
321	.name =		"earlyser",
322	.write =	early_serial_write,
323	.flags =	CON_PRINTBUFFER,
324	.index =	-1,
325};
326
327static void early_console_register(struct console *con, int keep_early)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
328{
329	if (con->index != -1) {
330		printk(KERN_CRIT "ERROR: earlyprintk= %s already used\n",
331		       con->name);
332		return;
333	}
334	early_console = con;
335	if (keep_early)
336		early_console->flags &= ~CON_BOOT;
337	else
338		early_console->flags |= CON_BOOT;
339	register_console(early_console);
340}
341
342static int __init setup_early_printk(char *buf)
343{
344	int keep;
345
346	if (!buf)
347		return 0;
348
349	if (early_console)
350		return 0;
 
351
352	keep = (strstr(buf, "keep") != NULL);
353
354	while (*buf != '\0') {
355		if (!strncmp(buf, "serial", 6)) {
356			buf += 6;
357			early_serial_init(buf);
358			early_console_register(&early_serial_console, keep);
359			if (!strncmp(buf, ",ttyS", 5))
360				buf += 5;
361		}
362		if (!strncmp(buf, "ttyS", 4)) {
363			early_serial_init(buf + 4);
364			early_console_register(&early_serial_console, keep);
365		}
366#ifdef CONFIG_PCI
367		if (!strncmp(buf, "pciserial", 9)) {
368			early_pci_serial_init(buf + 9);
369			early_console_register(&early_serial_console, keep);
370			buf += 9; /* Keep from match the above "serial" */
371		}
372#endif
373		if (!strncmp(buf, "vga", 3) &&
374		    boot_params.screen_info.orig_video_isVGA == 1) {
375			max_xpos = boot_params.screen_info.orig_video_cols;
376			max_ypos = boot_params.screen_info.orig_video_lines;
377			current_ypos = boot_params.screen_info.orig_y;
378			early_console_register(&early_vga_console, keep);
379		}
380#ifdef CONFIG_EARLY_PRINTK_DBGP
381		if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4))
382			early_console_register(&early_dbgp_console, keep);
383#endif
384#ifdef CONFIG_HVC_XEN
385		if (!strncmp(buf, "xen", 3))
386			early_console_register(&xenboot_console, keep);
387#endif
388#ifdef CONFIG_EARLY_PRINTK_USB_XDBC
389		if (!strncmp(buf, "xdbc", 4))
390			early_xdbc_parse_parameter(buf + 4, keep);
 
 
 
 
 
 
 
391#endif
392
393		buf++;
394	}
395	return 0;
396}
397
398early_param("earlyprintk", setup_early_printk);