xref: /openbmc/qemu/hw/riscv/virt.c (revision 4a9b31b8)
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/units.h"
23 #include "qemu/log.h"
24 #include "qemu/error-report.h"
25 #include "qapi/error.h"
26 #include "hw/hw.h"
27 #include "hw/boards.h"
28 #include "hw/loader.h"
29 #include "hw/sysbus.h"
30 #include "hw/char/serial.h"
31 #include "target/riscv/cpu.h"
32 #include "hw/riscv/riscv_htif.h"
33 #include "hw/riscv/riscv_hart.h"
34 #include "hw/riscv/sifive_plic.h"
35 #include "hw/riscv/sifive_clint.h"
36 #include "hw/riscv/sifive_test.h"
37 #include "hw/riscv/virt.h"
38 #include "chardev/char.h"
39 #include "sysemu/arch_init.h"
40 #include "sysemu/device_tree.h"
41 #include "exec/address-spaces.h"
42 #include "elf.h"
43 
44 #include <libfdt.h>
45 
46 static const struct MemmapEntry {
47     hwaddr base;
48     hwaddr size;
49 } virt_memmap[] = {
50     [VIRT_DEBUG] =    {        0x0,      0x100 },
51     [VIRT_MROM] =     {     0x1000,    0x11000 },
52     [VIRT_TEST] =     {   0x100000,     0x1000 },
53     [VIRT_CLINT] =    {  0x2000000,    0x10000 },
54     [VIRT_PLIC] =     {  0xc000000,  0x4000000 },
55     [VIRT_UART0] =    { 0x10000000,      0x100 },
56     [VIRT_VIRTIO] =   { 0x10001000,     0x1000 },
57     [VIRT_DRAM] =     { 0x80000000,        0x0 },
58 };
59 
60 static uint64_t load_kernel(const char *kernel_filename)
61 {
62     uint64_t kernel_entry, kernel_high;
63 
64     if (load_elf(kernel_filename, NULL, NULL,
65                  &kernel_entry, NULL, &kernel_high,
66                  0, EM_RISCV, 1, 0) < 0) {
67         error_report("could not load kernel '%s'", kernel_filename);
68         exit(1);
69     }
70     return kernel_entry;
71 }
72 
73 static hwaddr load_initrd(const char *filename, uint64_t mem_size,
74                           uint64_t kernel_entry, hwaddr *start)
75 {
76     int size;
77 
78     /* We want to put the initrd far enough into RAM that when the
79      * kernel is uncompressed it will not clobber the initrd. However
80      * on boards without much RAM we must ensure that we still leave
81      * enough room for a decent sized initrd, and on boards with large
82      * amounts of RAM we must avoid the initrd being so far up in RAM
83      * that it is outside lowmem and inaccessible to the kernel.
84      * So for boards with less  than 256MB of RAM we put the initrd
85      * halfway into RAM, and for boards with 256MB of RAM or more we put
86      * the initrd at 128MB.
87      */
88     *start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
89 
90     size = load_ramdisk(filename, *start, mem_size - *start);
91     if (size == -1) {
92         size = load_image_targphys(filename, *start, mem_size - *start);
93         if (size == -1) {
94             error_report("could not load ramdisk '%s'", filename);
95             exit(1);
96         }
97     }
98     return *start + size;
99 }
100 
101 static void *create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
102     uint64_t mem_size, const char *cmdline)
103 {
104     void *fdt;
105     int cpu;
106     uint32_t *cells;
107     char *nodename;
108     uint32_t plic_phandle, phandle = 1;
109     int i;
110 
111     fdt = s->fdt = create_device_tree(&s->fdt_size);
112     if (!fdt) {
113         error_report("create_device_tree() failed");
114         exit(1);
115     }
116 
117     qemu_fdt_setprop_string(fdt, "/", "model", "riscv-virtio,qemu");
118     qemu_fdt_setprop_string(fdt, "/", "compatible", "riscv-virtio");
119     qemu_fdt_setprop_cell(fdt, "/", "#size-cells", 0x2);
120     qemu_fdt_setprop_cell(fdt, "/", "#address-cells", 0x2);
121 
122     qemu_fdt_add_subnode(fdt, "/soc");
123     qemu_fdt_setprop(fdt, "/soc", "ranges", NULL, 0);
124     qemu_fdt_setprop_string(fdt, "/soc", "compatible", "simple-bus");
125     qemu_fdt_setprop_cell(fdt, "/soc", "#size-cells", 0x2);
126     qemu_fdt_setprop_cell(fdt, "/soc", "#address-cells", 0x2);
127 
128     nodename = g_strdup_printf("/memory@%lx",
129         (long)memmap[VIRT_DRAM].base);
130     qemu_fdt_add_subnode(fdt, nodename);
131     qemu_fdt_setprop_cells(fdt, nodename, "reg",
132         memmap[VIRT_DRAM].base >> 32, memmap[VIRT_DRAM].base,
133         mem_size >> 32, mem_size);
134     qemu_fdt_setprop_string(fdt, nodename, "device_type", "memory");
135     g_free(nodename);
136 
137     qemu_fdt_add_subnode(fdt, "/cpus");
138     qemu_fdt_setprop_cell(fdt, "/cpus", "timebase-frequency",
139                           SIFIVE_CLINT_TIMEBASE_FREQ);
140     qemu_fdt_setprop_cell(fdt, "/cpus", "#size-cells", 0x0);
141     qemu_fdt_setprop_cell(fdt, "/cpus", "#address-cells", 0x1);
142 
143     for (cpu = s->soc.num_harts - 1; cpu >= 0; cpu--) {
144         int cpu_phandle = phandle++;
145         nodename = g_strdup_printf("/cpus/cpu@%d", cpu);
146         char *intc = g_strdup_printf("/cpus/cpu@%d/interrupt-controller", cpu);
147         char *isa = riscv_isa_string(&s->soc.harts[cpu]);
148         qemu_fdt_add_subnode(fdt, nodename);
149         qemu_fdt_setprop_cell(fdt, nodename, "clock-frequency",
150                               VIRT_CLOCK_FREQ);
151         qemu_fdt_setprop_string(fdt, nodename, "mmu-type", "riscv,sv48");
152         qemu_fdt_setprop_string(fdt, nodename, "riscv,isa", isa);
153         qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv");
154         qemu_fdt_setprop_string(fdt, nodename, "status", "okay");
155         qemu_fdt_setprop_cell(fdt, nodename, "reg", cpu);
156         qemu_fdt_setprop_string(fdt, nodename, "device_type", "cpu");
157         qemu_fdt_add_subnode(fdt, intc);
158         qemu_fdt_setprop_cell(fdt, intc, "phandle", cpu_phandle);
159         qemu_fdt_setprop_cell(fdt, intc, "linux,phandle", cpu_phandle);
160         qemu_fdt_setprop_string(fdt, intc, "compatible", "riscv,cpu-intc");
161         qemu_fdt_setprop(fdt, intc, "interrupt-controller", NULL, 0);
162         qemu_fdt_setprop_cell(fdt, intc, "#interrupt-cells", 1);
163         g_free(isa);
164         g_free(intc);
165         g_free(nodename);
166     }
167 
168     cells =  g_new0(uint32_t, s->soc.num_harts * 4);
169     for (cpu = 0; cpu < s->soc.num_harts; cpu++) {
170         nodename =
171             g_strdup_printf("/cpus/cpu@%d/interrupt-controller", cpu);
172         uint32_t intc_phandle = qemu_fdt_get_phandle(fdt, nodename);
173         cells[cpu * 4 + 0] = cpu_to_be32(intc_phandle);
174         cells[cpu * 4 + 1] = cpu_to_be32(IRQ_M_SOFT);
175         cells[cpu * 4 + 2] = cpu_to_be32(intc_phandle);
176         cells[cpu * 4 + 3] = cpu_to_be32(IRQ_M_TIMER);
177         g_free(nodename);
178     }
179     nodename = g_strdup_printf("/soc/clint@%lx",
180         (long)memmap[VIRT_CLINT].base);
181     qemu_fdt_add_subnode(fdt, nodename);
182     qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv,clint0");
183     qemu_fdt_setprop_cells(fdt, nodename, "reg",
184         0x0, memmap[VIRT_CLINT].base,
185         0x0, memmap[VIRT_CLINT].size);
186     qemu_fdt_setprop(fdt, nodename, "interrupts-extended",
187         cells, s->soc.num_harts * sizeof(uint32_t) * 4);
188     g_free(cells);
189     g_free(nodename);
190 
191     plic_phandle = phandle++;
192     cells =  g_new0(uint32_t, s->soc.num_harts * 4);
193     for (cpu = 0; cpu < s->soc.num_harts; cpu++) {
194         nodename =
195             g_strdup_printf("/cpus/cpu@%d/interrupt-controller", cpu);
196         uint32_t intc_phandle = qemu_fdt_get_phandle(fdt, nodename);
197         cells[cpu * 4 + 0] = cpu_to_be32(intc_phandle);
198         cells[cpu * 4 + 1] = cpu_to_be32(IRQ_M_EXT);
199         cells[cpu * 4 + 2] = cpu_to_be32(intc_phandle);
200         cells[cpu * 4 + 3] = cpu_to_be32(IRQ_S_EXT);
201         g_free(nodename);
202     }
203     nodename = g_strdup_printf("/soc/interrupt-controller@%lx",
204         (long)memmap[VIRT_PLIC].base);
205     qemu_fdt_add_subnode(fdt, nodename);
206     qemu_fdt_setprop_cell(fdt, nodename, "#interrupt-cells", 1);
207     qemu_fdt_setprop_string(fdt, nodename, "compatible", "riscv,plic0");
208     qemu_fdt_setprop(fdt, nodename, "interrupt-controller", NULL, 0);
209     qemu_fdt_setprop(fdt, nodename, "interrupts-extended",
210         cells, s->soc.num_harts * sizeof(uint32_t) * 4);
211     qemu_fdt_setprop_cells(fdt, nodename, "reg",
212         0x0, memmap[VIRT_PLIC].base,
213         0x0, memmap[VIRT_PLIC].size);
214     qemu_fdt_setprop_string(fdt, nodename, "reg-names", "control");
215     qemu_fdt_setprop_cell(fdt, nodename, "riscv,max-priority", 7);
216     qemu_fdt_setprop_cell(fdt, nodename, "riscv,ndev", VIRTIO_NDEV);
217     qemu_fdt_setprop_cells(fdt, nodename, "phandle", plic_phandle);
218     qemu_fdt_setprop_cells(fdt, nodename, "linux,phandle", plic_phandle);
219     plic_phandle = qemu_fdt_get_phandle(fdt, nodename);
220     g_free(cells);
221     g_free(nodename);
222 
223     for (i = 0; i < VIRTIO_COUNT; i++) {
224         nodename = g_strdup_printf("/virtio_mmio@%lx",
225             (long)(memmap[VIRT_VIRTIO].base + i * memmap[VIRT_VIRTIO].size));
226         qemu_fdt_add_subnode(fdt, nodename);
227         qemu_fdt_setprop_string(fdt, nodename, "compatible", "virtio,mmio");
228         qemu_fdt_setprop_cells(fdt, nodename, "reg",
229             0x0, memmap[VIRT_VIRTIO].base + i * memmap[VIRT_VIRTIO].size,
230             0x0, memmap[VIRT_VIRTIO].size);
231         qemu_fdt_setprop_cells(fdt, nodename, "interrupt-parent", plic_phandle);
232         qemu_fdt_setprop_cells(fdt, nodename, "interrupts", VIRTIO_IRQ + i);
233         g_free(nodename);
234     }
235 
236     nodename = g_strdup_printf("/test@%lx",
237         (long)memmap[VIRT_TEST].base);
238     qemu_fdt_add_subnode(fdt, nodename);
239     qemu_fdt_setprop_string(fdt, nodename, "compatible", "sifive,test0");
240     qemu_fdt_setprop_cells(fdt, nodename, "reg",
241         0x0, memmap[VIRT_TEST].base,
242         0x0, memmap[VIRT_TEST].size);
243 
244     nodename = g_strdup_printf("/uart@%lx",
245         (long)memmap[VIRT_UART0].base);
246     qemu_fdt_add_subnode(fdt, nodename);
247     qemu_fdt_setprop_string(fdt, nodename, "compatible", "ns16550a");
248     qemu_fdt_setprop_cells(fdt, nodename, "reg",
249         0x0, memmap[VIRT_UART0].base,
250         0x0, memmap[VIRT_UART0].size);
251     qemu_fdt_setprop_cell(fdt, nodename, "clock-frequency", 3686400);
252         qemu_fdt_setprop_cells(fdt, nodename, "interrupt-parent", plic_phandle);
253         qemu_fdt_setprop_cells(fdt, nodename, "interrupts", UART0_IRQ);
254 
255     qemu_fdt_add_subnode(fdt, "/chosen");
256     qemu_fdt_setprop_string(fdt, "/chosen", "stdout-path", nodename);
257     if (cmdline) {
258         qemu_fdt_setprop_string(fdt, "/chosen", "bootargs", cmdline);
259     }
260     g_free(nodename);
261 
262     return fdt;
263 }
264 
265 static void riscv_virt_board_init(MachineState *machine)
266 {
267     const struct MemmapEntry *memmap = virt_memmap;
268 
269     RISCVVirtState *s = g_new0(RISCVVirtState, 1);
270     MemoryRegion *system_memory = get_system_memory();
271     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
272     MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
273     char *plic_hart_config;
274     size_t plic_hart_config_len;
275     int i;
276     void *fdt;
277 
278     /* Initialize SOC */
279     object_initialize_child(OBJECT(machine), "soc", &s->soc, sizeof(s->soc),
280                             TYPE_RISCV_HART_ARRAY, &error_abort, NULL);
281     object_property_set_str(OBJECT(&s->soc), VIRT_CPU, "cpu-type",
282                             &error_abort);
283     object_property_set_int(OBJECT(&s->soc), smp_cpus, "num-harts",
284                             &error_abort);
285     object_property_set_bool(OBJECT(&s->soc), true, "realized",
286                             &error_abort);
287 
288     /* register system main memory (actual RAM) */
289     memory_region_init_ram(main_mem, NULL, "riscv_virt_board.ram",
290                            machine->ram_size, &error_fatal);
291     memory_region_add_subregion(system_memory, memmap[VIRT_DRAM].base,
292         main_mem);
293 
294     /* create device tree */
295     fdt = create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
296 
297     /* boot rom */
298     memory_region_init_rom(mask_rom, NULL, "riscv_virt_board.mrom",
299                            memmap[VIRT_MROM].size, &error_fatal);
300     memory_region_add_subregion(system_memory, memmap[VIRT_MROM].base,
301                                 mask_rom);
302 
303     if (machine->kernel_filename) {
304         uint64_t kernel_entry = load_kernel(machine->kernel_filename);
305 
306         if (machine->initrd_filename) {
307             hwaddr start;
308             hwaddr end = load_initrd(machine->initrd_filename,
309                                      machine->ram_size, kernel_entry,
310                                      &start);
311             qemu_fdt_setprop_cell(fdt, "/chosen",
312                                   "linux,initrd-start", start);
313             qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-end",
314                                   end);
315         }
316     }
317 
318     /* reset vector */
319     uint32_t reset_vec[8] = {
320         0x00000297,                  /* 1:  auipc  t0, %pcrel_hi(dtb) */
321         0x02028593,                  /*     addi   a1, t0, %pcrel_lo(1b) */
322         0xf1402573,                  /*     csrr   a0, mhartid  */
323 #if defined(TARGET_RISCV32)
324         0x0182a283,                  /*     lw     t0, 24(t0) */
325 #elif defined(TARGET_RISCV64)
326         0x0182b283,                  /*     ld     t0, 24(t0) */
327 #endif
328         0x00028067,                  /*     jr     t0 */
329         0x00000000,
330         memmap[VIRT_DRAM].base,      /* start: .dword memmap[VIRT_DRAM].base */
331         0x00000000,
332                                      /* dtb: */
333     };
334 
335     /* copy in the reset vector in little_endian byte order */
336     for (i = 0; i < sizeof(reset_vec) >> 2; i++) {
337         reset_vec[i] = cpu_to_le32(reset_vec[i]);
338     }
339     rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
340                           memmap[VIRT_MROM].base, &address_space_memory);
341 
342     /* copy in the device tree */
343     if (fdt_pack(s->fdt) || fdt_totalsize(s->fdt) >
344             memmap[VIRT_MROM].size - sizeof(reset_vec)) {
345         error_report("not enough space to store device-tree");
346         exit(1);
347     }
348     qemu_fdt_dumpdtb(s->fdt, fdt_totalsize(s->fdt));
349     rom_add_blob_fixed_as("mrom.fdt", s->fdt, fdt_totalsize(s->fdt),
350                           memmap[VIRT_MROM].base + sizeof(reset_vec),
351                           &address_space_memory);
352 
353     /* create PLIC hart topology configuration string */
354     plic_hart_config_len = (strlen(VIRT_PLIC_HART_CONFIG) + 1) * smp_cpus;
355     plic_hart_config = g_malloc0(plic_hart_config_len);
356     for (i = 0; i < smp_cpus; i++) {
357         if (i != 0) {
358             strncat(plic_hart_config, ",", plic_hart_config_len);
359         }
360         strncat(plic_hart_config, VIRT_PLIC_HART_CONFIG, plic_hart_config_len);
361         plic_hart_config_len -= (strlen(VIRT_PLIC_HART_CONFIG) + 1);
362     }
363 
364     /* MMIO */
365     s->plic = sifive_plic_create(memmap[VIRT_PLIC].base,
366         plic_hart_config,
367         VIRT_PLIC_NUM_SOURCES,
368         VIRT_PLIC_NUM_PRIORITIES,
369         VIRT_PLIC_PRIORITY_BASE,
370         VIRT_PLIC_PENDING_BASE,
371         VIRT_PLIC_ENABLE_BASE,
372         VIRT_PLIC_ENABLE_STRIDE,
373         VIRT_PLIC_CONTEXT_BASE,
374         VIRT_PLIC_CONTEXT_STRIDE,
375         memmap[VIRT_PLIC].size);
376     sifive_clint_create(memmap[VIRT_CLINT].base,
377         memmap[VIRT_CLINT].size, smp_cpus,
378         SIFIVE_SIP_BASE, SIFIVE_TIMECMP_BASE, SIFIVE_TIME_BASE);
379     sifive_test_create(memmap[VIRT_TEST].base);
380 
381     for (i = 0; i < VIRTIO_COUNT; i++) {
382         sysbus_create_simple("virtio-mmio",
383             memmap[VIRT_VIRTIO].base + i * memmap[VIRT_VIRTIO].size,
384             qdev_get_gpio_in(DEVICE(s->plic), VIRTIO_IRQ + i));
385     }
386 
387     serial_mm_init(system_memory, memmap[VIRT_UART0].base,
388         0, qdev_get_gpio_in(DEVICE(s->plic), UART0_IRQ), 399193,
389         serial_hd(0), DEVICE_LITTLE_ENDIAN);
390 
391     g_free(plic_hart_config);
392 }
393 
394 static void riscv_virt_board_machine_init(MachineClass *mc)
395 {
396     mc->desc = "RISC-V VirtIO Board (Privileged ISA v1.10)";
397     mc->init = riscv_virt_board_init;
398     mc->max_cpus = 8; /* hardcoded limit in BBL */
399 }
400 
401 DEFINE_MACHINE("virt", riscv_virt_board_machine_init)
402