xref: /openbmc/qemu/hw/arm/armv7m.c (revision 1b111dc1)
1 /*
2  * ARMV7M System emulation.
3  *
4  * Copyright (c) 2006-2007 CodeSourcery.
5  * Written by Paul Brook
6  *
7  * This code is licensed under the GPL.
8  */
9 
10 #include "hw/sysbus.h"
11 #include "hw/arm/arm.h"
12 #include "hw/loader.h"
13 #include "elf.h"
14 #include "sysemu/qtest.h"
15 #include "qemu/error-report.h"
16 
17 /* Bitbanded IO.  Each word corresponds to a single bit.  */
18 
19 /* Get the byte address of the real memory for a bitband access.  */
20 static inline uint32_t bitband_addr(void * opaque, uint32_t addr)
21 {
22     uint32_t res;
23 
24     res = *(uint32_t *)opaque;
25     res |= (addr & 0x1ffffff) >> 5;
26     return res;
27 
28 }
29 
30 static uint32_t bitband_readb(void *opaque, hwaddr offset)
31 {
32     uint8_t v;
33     cpu_physical_memory_read(bitband_addr(opaque, offset), &v, 1);
34     return (v & (1 << ((offset >> 2) & 7))) != 0;
35 }
36 
37 static void bitband_writeb(void *opaque, hwaddr offset,
38                            uint32_t value)
39 {
40     uint32_t addr;
41     uint8_t mask;
42     uint8_t v;
43     addr = bitband_addr(opaque, offset);
44     mask = (1 << ((offset >> 2) & 7));
45     cpu_physical_memory_read(addr, &v, 1);
46     if (value & 1)
47         v |= mask;
48     else
49         v &= ~mask;
50     cpu_physical_memory_write(addr, &v, 1);
51 }
52 
53 static uint32_t bitband_readw(void *opaque, hwaddr offset)
54 {
55     uint32_t addr;
56     uint16_t mask;
57     uint16_t v;
58     addr = bitband_addr(opaque, offset) & ~1;
59     mask = (1 << ((offset >> 2) & 15));
60     mask = tswap16(mask);
61     cpu_physical_memory_read(addr, &v, 2);
62     return (v & mask) != 0;
63 }
64 
65 static void bitband_writew(void *opaque, hwaddr offset,
66                            uint32_t value)
67 {
68     uint32_t addr;
69     uint16_t mask;
70     uint16_t v;
71     addr = bitband_addr(opaque, offset) & ~1;
72     mask = (1 << ((offset >> 2) & 15));
73     mask = tswap16(mask);
74     cpu_physical_memory_read(addr, &v, 2);
75     if (value & 1)
76         v |= mask;
77     else
78         v &= ~mask;
79     cpu_physical_memory_write(addr, &v, 2);
80 }
81 
82 static uint32_t bitband_readl(void *opaque, hwaddr offset)
83 {
84     uint32_t addr;
85     uint32_t mask;
86     uint32_t v;
87     addr = bitband_addr(opaque, offset) & ~3;
88     mask = (1 << ((offset >> 2) & 31));
89     mask = tswap32(mask);
90     cpu_physical_memory_read(addr, &v, 4);
91     return (v & mask) != 0;
92 }
93 
94 static void bitband_writel(void *opaque, hwaddr offset,
95                            uint32_t value)
96 {
97     uint32_t addr;
98     uint32_t mask;
99     uint32_t v;
100     addr = bitband_addr(opaque, offset) & ~3;
101     mask = (1 << ((offset >> 2) & 31));
102     mask = tswap32(mask);
103     cpu_physical_memory_read(addr, &v, 4);
104     if (value & 1)
105         v |= mask;
106     else
107         v &= ~mask;
108     cpu_physical_memory_write(addr, &v, 4);
109 }
110 
111 static const MemoryRegionOps bitband_ops = {
112     .old_mmio = {
113         .read = { bitband_readb, bitband_readw, bitband_readl, },
114         .write = { bitband_writeb, bitband_writew, bitband_writel, },
115     },
116     .endianness = DEVICE_NATIVE_ENDIAN,
117 };
118 
119 #define TYPE_BITBAND "ARM,bitband-memory"
120 #define BITBAND(obj) OBJECT_CHECK(BitBandState, (obj), TYPE_BITBAND)
121 
122 typedef struct {
123     /*< private >*/
124     SysBusDevice parent_obj;
125     /*< public >*/
126 
127     MemoryRegion iomem;
128     uint32_t base;
129 } BitBandState;
130 
131 static int bitband_init(SysBusDevice *dev)
132 {
133     BitBandState *s = BITBAND(dev);
134 
135     memory_region_init_io(&s->iomem, OBJECT(s), &bitband_ops, &s->base,
136                           "bitband", 0x02000000);
137     sysbus_init_mmio(dev, &s->iomem);
138     return 0;
139 }
140 
141 static void armv7m_bitband_init(void)
142 {
143     DeviceState *dev;
144 
145     dev = qdev_create(NULL, TYPE_BITBAND);
146     qdev_prop_set_uint32(dev, "base", 0x20000000);
147     qdev_init_nofail(dev);
148     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 0x22000000);
149 
150     dev = qdev_create(NULL, TYPE_BITBAND);
151     qdev_prop_set_uint32(dev, "base", 0x40000000);
152     qdev_init_nofail(dev);
153     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 0x42000000);
154 }
155 
156 /* Board init.  */
157 
158 static void armv7m_reset(void *opaque)
159 {
160     ARMCPU *cpu = opaque;
161 
162     cpu_reset(CPU(cpu));
163 }
164 
165 /* Init CPU and memory for a v7-M based board.
166    flash_size and sram_size are in kb.
167    Returns the NVIC array.  */
168 
169 qemu_irq *armv7m_init(MemoryRegion *address_space_mem,
170                       int flash_size, int sram_size,
171                       const char *kernel_filename, const char *cpu_model)
172 {
173     ARMCPU *cpu;
174     CPUARMState *env;
175     DeviceState *nvic;
176     /* FIXME: make this local state.  */
177     static qemu_irq pic[64];
178     int image_size;
179     uint64_t entry;
180     uint64_t lowaddr;
181     int i;
182     int big_endian;
183     MemoryRegion *sram = g_new(MemoryRegion, 1);
184     MemoryRegion *flash = g_new(MemoryRegion, 1);
185     MemoryRegion *hack = g_new(MemoryRegion, 1);
186 
187     flash_size *= 1024;
188     sram_size *= 1024;
189 
190     if (cpu_model == NULL) {
191 	cpu_model = "cortex-m3";
192     }
193     cpu = cpu_arm_init(cpu_model);
194     if (cpu == NULL) {
195         fprintf(stderr, "Unable to find CPU definition\n");
196         exit(1);
197     }
198     env = &cpu->env;
199 
200 #if 0
201     /* > 32Mb SRAM gets complicated because it overlaps the bitband area.
202        We don't have proper commandline options, so allocate half of memory
203        as SRAM, up to a maximum of 32Mb, and the rest as code.  */
204     if (ram_size > (512 + 32) * 1024 * 1024)
205         ram_size = (512 + 32) * 1024 * 1024;
206     sram_size = (ram_size / 2) & TARGET_PAGE_MASK;
207     if (sram_size > 32 * 1024 * 1024)
208         sram_size = 32 * 1024 * 1024;
209     code_size = ram_size - sram_size;
210 #endif
211 
212     /* Flash programming is done via the SCU, so pretend it is ROM.  */
213     memory_region_init_ram(flash, NULL, "armv7m.flash", flash_size);
214     vmstate_register_ram_global(flash);
215     memory_region_set_readonly(flash, true);
216     memory_region_add_subregion(address_space_mem, 0, flash);
217     memory_region_init_ram(sram, NULL, "armv7m.sram", sram_size);
218     vmstate_register_ram_global(sram);
219     memory_region_add_subregion(address_space_mem, 0x20000000, sram);
220     armv7m_bitband_init();
221 
222     nvic = qdev_create(NULL, "armv7m_nvic");
223     env->nvic = nvic;
224     qdev_init_nofail(nvic);
225     sysbus_connect_irq(SYS_BUS_DEVICE(nvic), 0,
226                        qdev_get_gpio_in(DEVICE(cpu), ARM_CPU_IRQ));
227     for (i = 0; i < 64; i++) {
228         pic[i] = qdev_get_gpio_in(nvic, i);
229     }
230 
231 #ifdef TARGET_WORDS_BIGENDIAN
232     big_endian = 1;
233 #else
234     big_endian = 0;
235 #endif
236 
237     if (!kernel_filename && !qtest_enabled()) {
238         fprintf(stderr, "Guest image must be specified (using -kernel)\n");
239         exit(1);
240     }
241 
242     if (kernel_filename) {
243         image_size = load_elf(kernel_filename, NULL, NULL, &entry, &lowaddr,
244                               NULL, big_endian, ELF_MACHINE, 1);
245         if (image_size < 0) {
246             image_size = load_image_targphys(kernel_filename, 0, flash_size);
247             lowaddr = 0;
248         }
249         if (image_size < 0) {
250             error_report("Could not load kernel '%s'", kernel_filename);
251             exit(1);
252         }
253     }
254 
255     /* Hack to map an additional page of ram at the top of the address
256        space.  This stops qemu complaining about executing code outside RAM
257        when returning from an exception.  */
258     memory_region_init_ram(hack, NULL, "armv7m.hack", 0x1000);
259     vmstate_register_ram_global(hack);
260     memory_region_add_subregion(address_space_mem, 0xfffff000, hack);
261 
262     qemu_register_reset(armv7m_reset, cpu);
263     return pic;
264 }
265 
266 static Property bitband_properties[] = {
267     DEFINE_PROP_UINT32("base", BitBandState, base, 0),
268     DEFINE_PROP_END_OF_LIST(),
269 };
270 
271 static void bitband_class_init(ObjectClass *klass, void *data)
272 {
273     DeviceClass *dc = DEVICE_CLASS(klass);
274     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
275 
276     k->init = bitband_init;
277     dc->props = bitband_properties;
278 }
279 
280 static const TypeInfo bitband_info = {
281     .name          = TYPE_BITBAND,
282     .parent        = TYPE_SYS_BUS_DEVICE,
283     .instance_size = sizeof(BitBandState),
284     .class_init    = bitband_class_init,
285 };
286 
287 static void armv7m_register_types(void)
288 {
289     type_register_static(&bitband_info);
290 }
291 
292 type_init(armv7m_register_types)
293