xref: /netbsd-src/sys/arch/evbmips/mipssim/machdep.c (revision f36002f244a49908fef9cba8789032bdbf48d572)
1 /* $NetBSD: machdep.c,v 1.5 2024/03/05 14:15:31 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2001,2021 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe and Simon Burge.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.5 2024/03/05 14:15:31 thorpej Exp $");
34 
35 #include "opt_ddb.h"
36 #include "opt_kgdb.h"
37 #include "opt_modular.h"
38 
39 #include <sys/param.h>
40 #include <sys/boot_flag.h>
41 #include <sys/bus.h>
42 #include <sys/cpu.h>
43 #include <sys/device.h>
44 #include <sys/kcore.h>
45 #include <sys/kernel.h>
46 #include <sys/ksyms.h>
47 #include <sys/mount.h>
48 #include <sys/mutex.h>
49 #include <sys/reboot.h>
50 #include <sys/termios.h>
51 
52 #include <uvm/uvm_extern.h>
53 
54 #include <dev/cons.h>
55 #include <dev/ic/comvar.h>
56 #include <dev/ic/ns16450reg.h>
57 
58 #include <evbmips/mipssim/mipssimreg.h>
59 #include <evbmips/mipssim/mipssimvar.h>
60 
61 #include "ksyms.h"
62 
63 #if NKSYMS || defined(DDB) || defined(MODULAR)
64 #include <mips/db_machdep.h>
65 #include <ddb/db_extern.h>
66 #endif
67 
68 #include <mips/cache.h>
69 #include <mips/locore.h>
70 #include <mips/cpuregs.h>
71 
72 
73 #define	COMCNRATE	115200		/* not important, emulated device */
74 #define	COM_FREQ	1843200		/* not important, emulated device */
75 
76 /*
77  * QEMU/mipssim sets the CPU frequency to 6 MHz for 64-bit guests and
78  * 12 MHz for 32-bit guests.
79  */
80 #ifdef _LP64
81 #define	CPU_FREQ	6	/* MHz */
82 #else
83 #define	CPU_FREQ	12	/* MHz */
84 #endif
85 
86 /* XXX move phys map decl to a general mips location */
87 /* Maps for VM objects. */
88 struct vm_map *phys_map = NULL;
89 
90 struct mipssim_config mipssim_configuration;
91 
92 /* XXX move mem cluster decls to a general mips location */
93 int mem_cluster_cnt;
94 phys_ram_seg_t mem_clusters[VM_PHYSSEG_MAX];
95 
96 /* XXX move mach_init() prototype to general mips header file */
97 void		mach_init(u_long, u_long, u_long, u_long);
98 static void	mach_init_memory(void);
99 
100 /*
101  * Provide a very simple output-only console driver so that we can
102  * use printf() before the "real" console is initialised.
103  */
104 static void uart_putc(dev_t, int);
105 static struct consdev early_console = {
106 	.cn_putc = uart_putc,
107 	.cn_dev = makedev(0, 0),
108 	.cn_pri = CN_DEAD
109 };
110 
111 static void
uart_putc(dev_t dev,int c)112 uart_putc(dev_t dev, int c)
113 {
114 	volatile uint8_t *data = (void *)MIPS_PHYS_TO_KSEG1(
115 	    MIPSSIM_ISA_IO_BASE + MIPSSIM_UART0_ADDR + com_data);
116 
117 	*data = (uint8_t)c;
118 	/* emulated UART, don't need to wait for output to drain */
119 }
120 
121 static void
cal_timer(void)122 cal_timer(void)
123 {
124 	uint32_t cntfreq;
125 
126 	cntfreq = curcpu()->ci_cpu_freq = CPU_FREQ * 1000 * 1000;
127 
128 	if (mips_options.mips_cpu_flags & CPU_MIPS_DOUBLE_COUNT)
129 		cntfreq /= 2;
130 
131 	curcpu()->ci_cctr_freq = cntfreq;
132 	curcpu()->ci_cycles_per_hz = (cntfreq + hz / 2) / hz;
133 
134 	/* Compute number of cycles per 1us (1/MHz). 0.5MHz is for roundup. */
135 	curcpu()->ci_divisor_delay = ((cntfreq + 500000) / 1000000);
136 }
137 
138 /*
139  *
140  */
141 void
mach_init(u_long arg0,u_long arg1,u_long arg2,u_long arg3)142 mach_init(u_long arg0, u_long arg1, u_long arg2, u_long arg3)
143 {
144 	struct mipssim_config *mcp = &mipssim_configuration;
145 	void *kernend;
146 	extern char edata[], end[];	/* XXX */
147 
148 	kernend = (void *)mips_round_page(end);
149 
150 	/* Zero BSS.  QEMU appears to leave some memory uninitialised. */
151 	memset(edata, 0, end - edata);
152 
153 	/* enough of a console for printf() to work */
154 	cn_tab = &early_console;
155 
156 	/* set CPU model info for sysctl_hw */
157 	cpu_setmodel("MIPSSIM");
158 
159 	mips_vector_init(NULL, false);
160 
161 	/* must be after CPU is identified in mips_vector_init() */
162 	cal_timer();
163 
164 	uvm_md_init();
165 
166 	/*
167 	 * Initialize bus space tags and bring up the main console.
168 	 */
169 	mipssim_bus_io_init(&mcp->mc_iot, mcp);
170 	mipssim_dma_init(mcp);
171 
172 	if (comcnattach(&mcp->mc_iot, MIPSSIM_UART0_ADDR, COMCNRATE,
173 	    COM_FREQ, COM_TYPE_NORMAL,
174 	    (TTYDEF_CFLAG & ~(CSIZE | PARENB)) | CS8) != 0)
175 		panic("unable to initialize serial console");
176 
177 	/*
178 	 * No way of passing arguments in mipssim.
179 	 */
180 	boothowto = RB_AUTOBOOT;
181 #ifdef KADB
182 	boothowto |= RB_KDB;
183 #endif
184 
185 	mach_init_memory();
186 
187 	/*
188 	 * Load the available pages into the VM system.
189 	 */
190 	mips_page_physload(MIPS_KSEG0_START, (vaddr_t)kernend,
191 	    mem_clusters, mem_cluster_cnt, NULL, 0);
192 
193 	/*
194 	 * Initialize message buffer (at end of core).
195 	 */
196 	mips_init_msgbuf();
197 
198 	/*
199 	 * Initialize the virtual memory system.
200 	 */
201 	pmap_bootstrap();
202 
203 	/*
204 	 * Allocate uarea page for lwp0 and set it.
205 	 */
206 	mips_init_lwp0_uarea();
207 
208 	/*
209 	 * Initialize debuggers, and break into them, if appropriate.
210 	 */
211 #ifdef DDB
212 	if (boothowto & RB_KDB)
213 		Debugger();
214 #endif
215 }
216 
217 /*
218  * qemu for mipssim doesn't have a way of passing in the memory size, so
219  * we probe.  lwp0 hasn't been set up this early, so use a dummy pcb to
220  * allow badaddr() to function.  Limit total RAM to just before the IO
221  * memory at MIPSSIM_ISA_IO_BASE.
222  */
223 static void
mach_init_memory(void)224 mach_init_memory(void)
225 {
226 	struct lwp *l = curlwp;
227 	struct pcb dummypcb;
228 	psize_t memsize;
229 	size_t addr;
230 	uint32_t *memptr;
231 	extern char end[];	/* XXX */
232 #ifdef MIPS64
233 	size_t highaddr;
234 #endif
235 
236 	l->l_addr = &dummypcb;
237 	memsize = roundup2(MIPS_KSEG0_TO_PHYS((uintptr_t)(end)), 1024 * 1024);
238 
239 	for (addr = memsize; addr < MIPSSIM_ISA_IO_BASE; addr += 1024 * 1024) {
240 #ifdef MEM_DEBUG
241 		printf("test %zd MB\n", addr / 1024 * 1024);
242 #endif
243 		memptr = (void *)MIPS_PHYS_TO_KSEG1(addr - sizeof(*memptr));
244 
245 		if (badaddr(memptr, sizeof(uint32_t)) < 0)
246 			break;
247 
248 		memsize = addr;
249 	}
250 	l->l_addr = NULL;
251 
252 	physmem = btoc(memsize);
253 
254 	mem_clusters[0].start = PAGE_SIZE;
255 	mem_clusters[0].size = memsize - PAGE_SIZE;
256 	mem_cluster_cnt = 1;
257 
258 #ifdef _LP64
259 	/* probe for more memory above ISA I/O "hole" */
260 	l->l_addr = &dummypcb;
261 
262 	for (highaddr = addr = MIPSSIM_MORE_MEM_BASE;
263 	    addr < MIPSSIM_MORE_MEM_END;
264 	    addr += 1024 * 1024) {
265 		memptr = (void *)MIPS_PHYS_TO_XKPHYS(CCA_CACHEABLE,
266 						addr - sizeof(*memptr));
267 		if (badaddr(memptr, sizeof(uint32_t)) < 0)
268 			break;
269 
270 		highaddr = addr;
271 #ifdef MEM_DEBUG
272 		printf("probed %zd MB\n", (addr - MIPSSIM_MORE_MEM_BASE)
273 					/ 1024 * 1024);
274 #endif
275 	}
276 	l->l_addr = NULL;
277 
278 	if (highaddr != MIPSSIM_MORE_MEM_BASE) {
279 		mem_clusters[1].start = MIPSSIM_MORE_MEM_BASE;
280 		mem_clusters[1].size = highaddr - MIPSSIM_MORE_MEM_BASE;
281 		mem_cluster_cnt++;
282 		physmem += btoc(mem_clusters[1].size);
283 		memsize += mem_clusters[1].size;
284 	}
285 #endif /* _LP64 */
286 
287 	printf("Memory size: 0x%" PRIxPSIZE " (%" PRIdPSIZE " MB)\n",
288 	    memsize, memsize / 1024 / 1024);
289 }
290 
291 void
consinit(void)292 consinit(void)
293 {
294 	/*
295 	 * Everything related to console initialization is done
296 	 * in mach_init().
297 	 */
298 }
299 
300 void
cpu_startup(void)301 cpu_startup(void)
302 {
303 
304 	/*
305 	 * Do the common startup items.
306 	 */
307 	cpu_startup_common();
308 }
309 
310 /* XXX try to make this evbmips generic */
311 void
cpu_reboot(int howto,char * bootstr)312 cpu_reboot(int howto, char *bootstr)
313 {
314 	static int waittime = -1;
315 
316 	/* Take a snapshot before clobbering any registers. */
317 	savectx(curpcb);
318 
319 	/* If "always halt" was specified as a boot flag, obey. */
320 	if (boothowto & RB_HALT)
321 		howto |= RB_HALT;
322 
323 	boothowto = howto;
324 
325 	/* If system is cold, just halt. */
326 	if (cold) {
327 		boothowto |= RB_HALT;
328 		goto haltsys;
329 	}
330 
331 	if ((boothowto & RB_NOSYNC) == 0 && waittime < 0) {
332 		waittime = 0;
333 
334 		/*
335 		 * Synchronize the disks....
336 		 */
337 		vfs_shutdown();
338 	}
339 
340 	/* Disable interrupts. */
341 	splhigh();
342 
343 	if (boothowto & RB_DUMP)
344 		dumpsys();
345 
346 haltsys:
347 	/* Run any shutdown hooks. */
348 	doshutdownhooks();
349 
350 	/*
351 	 * Firmware may autoboot (depending on settings), and we cannot pass
352 	 * flags to it (at least I haven't figured out how to yet), so
353 	 * we "pseudo-halt" now.
354 	 */
355 	if (boothowto & RB_HALT) {
356 		printf("\n");
357 		printf("The operating system has halted.\n");
358 		printf("Please press any key to reboot.\n\n");
359 		cnpollc(1);	/* For proper keyboard command handling */
360 		cngetc();
361 		cnpollc(0);
362 	}
363 
364 	printf("resetting...\n\n");
365 	__asm volatile("jr	%0" :: "r"(MIPS_RESET_EXC_VEC));
366 	printf("Oops, back from reset\n\nSpinning...");
367 	for (;;)
368 		/* spin forever */ ;	/* XXX */
369 	/*NOTREACHED*/
370 }
371