xref: /openbmc/qemu/hw/riscv/virt.c (revision fe7f9b8e)
1 /*
2  * QEMU RISC-V VirtIO Board
3  *
4  * Copyright (c) 2017 SiFive, Inc.
5  *
6  * RISC-V machine with 16550a UART and VirtIO MMIO
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms and conditions of the GNU General Public License,
10  * version 2 or later, as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15  * more details.
16  *
17  * You should have received a copy of the GNU General Public License along with
18  * this program.  If not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qemu/log.h"
23 #include "qemu/error-report.h"
24 #include "qapi/error.h"
25 #include "hw/hw.h"
26 #include "hw/boards.h"
27 #include "hw/loader.h"
28 #include "hw/sysbus.h"
29 #include "hw/char/serial.h"
30 #include "target/riscv/cpu.h"
31 #include "hw/riscv/riscv_htif.h"
32 #include "hw/riscv/riscv_hart.h"
33 #include "hw/riscv/sifive_plic.h"
34 #include "hw/riscv/sifive_clint.h"
35 #include "hw/riscv/sifive_test.h"
36 #include "hw/riscv/virt.h"
37 #include "chardev/char.h"
38 #include "sysemu/arch_init.h"
39 #include "sysemu/device_tree.h"
40 #include "exec/address-spaces.h"
41 #include "elf.h"
42 
43 #include <libfdt.h>
44 
45 static const struct MemmapEntry {
46     hwaddr base;
47     hwaddr size;
48 } virt_memmap[] = {
49     [VIRT_DEBUG] =    {        0x0,      0x100 },
50     [VIRT_MROM] =     {     0x1000,    0x11000 },
51     [VIRT_TEST] =     {   0x100000,     0x1000 },
52     [VIRT_CLINT] =    {  0x2000000,    0x10000 },
53     [VIRT_PLIC] =     {  0xc000000,  0x4000000 },
54     [VIRT_UART0] =    { 0x10000000,      0x100 },
55     [VIRT_VIRTIO] =   { 0x10001000,     0x1000 },
56     [VIRT_DRAM] =     { 0x80000000,        0x0 },
57 };
58 
59 static uint64_t load_kernel(const char *kernel_filename)
60 {
61     uint64_t kernel_entry, kernel_high;
62 
63     if (load_elf(kernel_filename, NULL, NULL,
64                  &kernel_entry, NULL, &kernel_high,
65                  0, EM_RISCV, 1, 0) < 0) {
66         error_report("qemu: could not load kernel '%s'", kernel_filename);
67         exit(1);
68     }
69     return kernel_entry;
70 }
71 
72 static hwaddr load_initrd(const char *filename, uint64_t mem_size,
73                           uint64_t kernel_entry, hwaddr *start)
74 {
75     int size;
76 
77     /* We want to put the initrd far enough into RAM that when the
78      * kernel is uncompressed it will not clobber the initrd. However
79      * on boards without much RAM we must ensure that we still leave
80      * enough room for a decent sized initrd, and on boards with large
81      * amounts of RAM we must avoid the initrd being so far up in RAM
82      * that it is outside lowmem and inaccessible to the kernel.
83      * So for boards with less  than 256MB of RAM we put the initrd
84      * halfway into RAM, and for boards with 256MB of RAM or more we put
85      * the initrd at 128MB.
86      */
87     *start = kernel_entry + MIN(mem_size / 2, 128 * 1024 * 1024);
88 
89     size = load_ramdisk(filename, *start, mem_size - *start);
90     if (size == -1) {
91         size = load_image_targphys(filename, *start, mem_size - *start);
92         if (size == -1) {
93             error_report("qemu: could not load ramdisk '%s'", filename);
94             exit(1);
95         }
96     }
97     return *start + size;
98 }
99 
100 static void *create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
101     uint64_t mem_size, const char *cmdline)
102 {
103     void *fdt;
104     int cpu;
105     uint32_t *cells;
106     char *nodename;
107     uint32_t plic_phandle, phandle = 1;
108     int i;
109 
110     fdt = s->fdt = create_device_tree(&s->fdt_size);
111     if (!fdt) {
112         error_report("create_device_tree() failed");
113         exit(1);
114     }
115 
116     qemu_fdt_setprop_string(fdt, "/", "model", "riscv-virtio,qemu");
117     qemu_fdt_setprop_string(fdt, "/", "compatible", "riscv-virtio");
118     qemu_fdt_setprop_cell(fdt, "/", "#size-cells", 0x2);
119     qemu_fdt_setprop_cell(fdt, "/", "#address-cells", 0x2);
120 
121     qemu_fdt_add_subnode(fdt, "/soc");
122     qemu_fdt_setprop(fdt, "/soc", "ranges", NULL, 0);
123     qemu_fdt_setprop_string(fdt, "/soc", "compatible", "riscv-virtio-soc");
124     qemu_fdt_setprop_cell(fdt, "/soc", "#size-cells", 0x2);
125     qemu_fdt_setprop_cell(fdt, "/soc", "#address-cells", 0x2);
126 
127     nodename = g_strdup_printf("/memory@%lx",
128         (long)memmap[VIRT_DRAM].base);
129     qemu_fdt_add_subnode(fdt, nodename);
130     qemu_fdt_setprop_cells(fdt, nodename, "reg",
131         memmap[VIRT_DRAM].base >> 32, memmap[VIRT_DRAM].base,
132         mem_size >> 32, mem_size);
133     qemu_fdt_setprop_string(fdt, nodename, "device_type", "memory");
134     g_free(nodename);
135 
136     qemu_fdt_add_subnode(fdt, "/cpus");
137     qemu_fdt_setprop_cell(fdt, "/cpus", "timebase-frequency",
138                           SIFIVE_CLINT_TIMEBASE_FREQ);
139     qemu_fdt_setprop_cell(fdt, "/cpus", "#size-cells", 0x0);
140     qemu_fdt_setprop_cell(fdt, "/cpus", "#address-cells", 0x1);
141 
142     for (cpu = s->soc.num_harts - 1; cpu >= 0; cpu--) {
143         int cpu_phandle = phandle++;
144         nodename = g_strdup_printf("/cpus/cpu@%d", cpu);
145         char *intc = g_strdup_printf("/cpus/cpu@%d/interrupt-controller", cpu);
146         char *isa = riscv_isa_string(&s->soc.harts[cpu]);
147         qemu_fdt_add_subnode(fdt, nodename);
148         qemu_fdt_setprop_cell(fdt, nodename, "clock-frequency",
149                               VIRT_CLOCK_FREQ);
150         qemu_fdt_setprop_string(fdt, nodename, "mmu-type", "riscv,sv48");
151         qemu_fdt_setprop_string(fdt, nodename, "riscv,isa", isa);
152         qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv");
153         qemu_fdt_setprop_string(fdt, nodename, "status", "okay");
154         qemu_fdt_setprop_cell(fdt, nodename, "reg", cpu);
155         qemu_fdt_setprop_string(fdt, nodename, "device_type", "cpu");
156         qemu_fdt_add_subnode(fdt, intc);
157         qemu_fdt_setprop_cell(fdt, intc, "phandle", cpu_phandle);
158         qemu_fdt_setprop_cell(fdt, intc, "linux,phandle", cpu_phandle);
159         qemu_fdt_setprop_string(fdt, intc, "compatible", "riscv,cpu-intc");
160         qemu_fdt_setprop(fdt, intc, "interrupt-controller", NULL, 0);
161         qemu_fdt_setprop_cell(fdt, intc, "#interrupt-cells", 1);
162         g_free(isa);
163         g_free(intc);
164         g_free(nodename);
165     }
166 
167     cells =  g_new0(uint32_t, s->soc.num_harts * 4);
168     for (cpu = 0; cpu < s->soc.num_harts; cpu++) {
169         nodename =
170             g_strdup_printf("/cpus/cpu@%d/interrupt-controller", cpu);
171         uint32_t intc_phandle = qemu_fdt_get_phandle(fdt, nodename);
172         cells[cpu * 4 + 0] = cpu_to_be32(intc_phandle);
173         cells[cpu * 4 + 1] = cpu_to_be32(IRQ_M_SOFT);
174         cells[cpu * 4 + 2] = cpu_to_be32(intc_phandle);
175         cells[cpu * 4 + 3] = cpu_to_be32(IRQ_M_TIMER);
176         g_free(nodename);
177     }
178     nodename = g_strdup_printf("/soc/clint@%lx",
179         (long)memmap[VIRT_CLINT].base);
180     qemu_fdt_add_subnode(fdt, nodename);
181     qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv,clint0");
182     qemu_fdt_setprop_cells(fdt, nodename, "reg",
183         0x0, memmap[VIRT_CLINT].base,
184         0x0, memmap[VIRT_CLINT].size);
185     qemu_fdt_setprop(fdt, nodename, "interrupts-extended",
186         cells, s->soc.num_harts * sizeof(uint32_t) * 4);
187     g_free(cells);
188     g_free(nodename);
189 
190     plic_phandle = phandle++;
191     cells =  g_new0(uint32_t, s->soc.num_harts * 4);
192     for (cpu = 0; cpu < s->soc.num_harts; cpu++) {
193         nodename =
194             g_strdup_printf("/cpus/cpu@%d/interrupt-controller", cpu);
195         uint32_t intc_phandle = qemu_fdt_get_phandle(fdt, nodename);
196         cells[cpu * 4 + 0] = cpu_to_be32(intc_phandle);
197         cells[cpu * 4 + 1] = cpu_to_be32(IRQ_M_EXT);
198         cells[cpu * 4 + 2] = cpu_to_be32(intc_phandle);
199         cells[cpu * 4 + 3] = cpu_to_be32(IRQ_S_EXT);
200         g_free(nodename);
201     }
202     nodename = g_strdup_printf("/soc/interrupt-controller@%lx",
203         (long)memmap[VIRT_PLIC].base);
204     qemu_fdt_add_subnode(fdt, nodename);
205     qemu_fdt_setprop_cell(fdt, nodename, "#interrupt-cells", 1);
206     qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv,plic0");
207     qemu_fdt_setprop(fdt, nodename, "interrupt-controller", NULL, 0);
208     qemu_fdt_setprop(fdt, nodename, "interrupts-extended",
209         cells, s->soc.num_harts * sizeof(uint32_t) * 4);
210     qemu_fdt_setprop_cells(fdt, nodename, "reg",
211         0x0, memmap[VIRT_PLIC].base,
212         0x0, memmap[VIRT_PLIC].size);
213     qemu_fdt_setprop_string(fdt, nodename, "reg-names", "control");
214     qemu_fdt_setprop_cell(fdt, nodename, "riscv,max-priority", 7);
215     qemu_fdt_setprop_cell(fdt, nodename, "riscv,ndev", VIRTIO_NDEV);
216     qemu_fdt_setprop_cells(fdt, nodename, "phandle", plic_phandle);
217     qemu_fdt_setprop_cells(fdt, nodename, "linux,phandle", plic_phandle);
218     plic_phandle = qemu_fdt_get_phandle(fdt, nodename);
219     g_free(cells);
220     g_free(nodename);
221 
222     for (i = 0; i < VIRTIO_COUNT; i++) {
223         nodename = g_strdup_printf("/virtio_mmio@%lx",
224             (long)(memmap[VIRT_VIRTIO].base + i * memmap[VIRT_VIRTIO].size));
225         qemu_fdt_add_subnode(fdt, nodename);
226         qemu_fdt_setprop_string(fdt, nodename, "compatible", "virtio,mmio");
227         qemu_fdt_setprop_cells(fdt, nodename, "reg",
228             0x0, memmap[VIRT_VIRTIO].base + i * memmap[VIRT_VIRTIO].size,
229             0x0, memmap[VIRT_VIRTIO].size);
230         qemu_fdt_setprop_cells(fdt, nodename, "interrupt-parent", plic_phandle);
231         qemu_fdt_setprop_cells(fdt, nodename, "interrupts", VIRTIO_IRQ + i);
232         g_free(nodename);
233     }
234 
235     nodename = g_strdup_printf("/test@%lx",
236         (long)memmap[VIRT_TEST].base);
237     qemu_fdt_add_subnode(fdt, nodename);
238     qemu_fdt_setprop_string(fdt, nodename, "compatible", "sifive,test0");
239     qemu_fdt_setprop_cells(fdt, nodename, "reg",
240         0x0, memmap[VIRT_TEST].base,
241         0x0, memmap[VIRT_TEST].size);
242 
243     nodename = g_strdup_printf("/uart@%lx",
244         (long)memmap[VIRT_UART0].base);
245     qemu_fdt_add_subnode(fdt, nodename);
246     qemu_fdt_setprop_string(fdt, nodename, "compatible", "ns16550a");
247     qemu_fdt_setprop_cells(fdt, nodename, "reg",
248         0x0, memmap[VIRT_UART0].base,
249         0x0, memmap[VIRT_UART0].size);
250     qemu_fdt_setprop_cell(fdt, nodename, "clock-frequency", 3686400);
251         qemu_fdt_setprop_cells(fdt, nodename, "interrupt-parent", plic_phandle);
252         qemu_fdt_setprop_cells(fdt, nodename, "interrupts", UART0_IRQ);
253 
254     qemu_fdt_add_subnode(fdt, "/chosen");
255     qemu_fdt_setprop_string(fdt, "/chosen", "stdout-path", nodename);
256     qemu_fdt_setprop_string(fdt, "/chosen", "bootargs", cmdline);
257     g_free(nodename);
258 
259     return fdt;
260 }
261 
262 static void riscv_virt_board_init(MachineState *machine)
263 {
264     const struct MemmapEntry *memmap = virt_memmap;
265 
266     RISCVVirtState *s = g_new0(RISCVVirtState, 1);
267     MemoryRegion *system_memory = get_system_memory();
268     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
269     MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
270     char *plic_hart_config;
271     size_t plic_hart_config_len;
272     int i;
273     void *fdt;
274 
275     /* Initialize SOC */
276     object_initialize(&s->soc, sizeof(s->soc), TYPE_RISCV_HART_ARRAY);
277     object_property_add_child(OBJECT(machine), "soc", OBJECT(&s->soc),
278                               &error_abort);
279     object_property_set_str(OBJECT(&s->soc), VIRT_CPU, "cpu-type",
280                             &error_abort);
281     object_property_set_int(OBJECT(&s->soc), smp_cpus, "num-harts",
282                             &error_abort);
283     object_property_set_bool(OBJECT(&s->soc), true, "realized",
284                             &error_abort);
285 
286     /* register system main memory (actual RAM) */
287     memory_region_init_ram(main_mem, NULL, "riscv_virt_board.ram",
288                            machine->ram_size, &error_fatal);
289     memory_region_add_subregion(system_memory, memmap[VIRT_DRAM].base,
290         main_mem);
291 
292     /* create device tree */
293     fdt = create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
294 
295     /* boot rom */
296     memory_region_init_rom(mask_rom, NULL, "riscv_virt_board.mrom",
297                            memmap[VIRT_MROM].size, &error_fatal);
298     memory_region_add_subregion(system_memory, memmap[VIRT_MROM].base,
299                                 mask_rom);
300 
301     if (machine->kernel_filename) {
302         uint64_t kernel_entry = load_kernel(machine->kernel_filename);
303 
304         if (machine->initrd_filename) {
305             hwaddr start;
306             hwaddr end = load_initrd(machine->initrd_filename,
307                                      machine->ram_size, kernel_entry,
308                                      &start);
309             qemu_fdt_setprop_cell(fdt, "/chosen",
310                                   "linux,initrd-start", start);
311             qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-end",
312                                   end);
313         }
314     }
315 
316     /* reset vector */
317     uint32_t reset_vec[8] = {
318         0x00000297,                  /* 1:  auipc  t0, %pcrel_hi(dtb) */
319         0x02028593,                  /*     addi   a1, t0, %pcrel_lo(1b) */
320         0xf1402573,                  /*     csrr   a0, mhartid  */
321 #if defined(TARGET_RISCV32)
322         0x0182a283,                  /*     lw     t0, 24(t0) */
323 #elif defined(TARGET_RISCV64)
324         0x0182b283,                  /*     ld     t0, 24(t0) */
325 #endif
326         0x00028067,                  /*     jr     t0 */
327         0x00000000,
328         memmap[VIRT_DRAM].base,      /* start: .dword memmap[VIRT_DRAM].base */
329         0x00000000,
330                                      /* dtb: */
331     };
332 
333     /* copy in the reset vector in little_endian byte order */
334     for (i = 0; i < sizeof(reset_vec) >> 2; i++) {
335         reset_vec[i] = cpu_to_le32(reset_vec[i]);
336     }
337     rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
338                           memmap[VIRT_MROM].base, &address_space_memory);
339 
340     /* copy in the device tree */
341     if (fdt_pack(s->fdt) || fdt_totalsize(s->fdt) >
342             memmap[VIRT_MROM].size - sizeof(reset_vec)) {
343         error_report("not enough space to store device-tree");
344         exit(1);
345     }
346     qemu_fdt_dumpdtb(s->fdt, fdt_totalsize(s->fdt));
347     rom_add_blob_fixed_as("mrom.fdt", s->fdt, fdt_totalsize(s->fdt),
348                           memmap[VIRT_MROM].base + sizeof(reset_vec),
349                           &address_space_memory);
350 
351     /* create PLIC hart topology configuration string */
352     plic_hart_config_len = (strlen(VIRT_PLIC_HART_CONFIG) + 1) * smp_cpus;
353     plic_hart_config = g_malloc0(plic_hart_config_len);
354     for (i = 0; i < smp_cpus; i++) {
355         if (i != 0) {
356             strncat(plic_hart_config, ",", plic_hart_config_len);
357         }
358         strncat(plic_hart_config, VIRT_PLIC_HART_CONFIG, plic_hart_config_len);
359         plic_hart_config_len -= (strlen(VIRT_PLIC_HART_CONFIG) + 1);
360     }
361 
362     /* MMIO */
363     s->plic = sifive_plic_create(memmap[VIRT_PLIC].base,
364         plic_hart_config,
365         VIRT_PLIC_NUM_SOURCES,
366         VIRT_PLIC_NUM_PRIORITIES,
367         VIRT_PLIC_PRIORITY_BASE,
368         VIRT_PLIC_PENDING_BASE,
369         VIRT_PLIC_ENABLE_BASE,
370         VIRT_PLIC_ENABLE_STRIDE,
371         VIRT_PLIC_CONTEXT_BASE,
372         VIRT_PLIC_CONTEXT_STRIDE,
373         memmap[VIRT_PLIC].size);
374     sifive_clint_create(memmap[VIRT_CLINT].base,
375         memmap[VIRT_CLINT].size, smp_cpus,
376         SIFIVE_SIP_BASE, SIFIVE_TIMECMP_BASE, SIFIVE_TIME_BASE);
377     sifive_test_create(memmap[VIRT_TEST].base);
378 
379     for (i = 0; i < VIRTIO_COUNT; i++) {
380         sysbus_create_simple("virtio-mmio",
381             memmap[VIRT_VIRTIO].base + i * memmap[VIRT_VIRTIO].size,
382             SIFIVE_PLIC(s->plic)->irqs[VIRTIO_IRQ + i]);
383     }
384 
385     serial_mm_init(system_memory, memmap[VIRT_UART0].base,
386         0, SIFIVE_PLIC(s->plic)->irqs[UART0_IRQ], 399193,
387         serial_hd(0), DEVICE_LITTLE_ENDIAN);
388 }
389 
390 static void riscv_virt_board_machine_init(MachineClass *mc)
391 {
392     mc->desc = "RISC-V VirtIO Board (Privileged ISA v1.10)";
393     mc->init = riscv_virt_board_init;
394     mc->max_cpus = 8; /* hardcoded limit in BBL */
395 }
396 
397 DEFINE_MACHINE("virt", riscv_virt_board_machine_init)
398