xref: /openbmc/qemu/hw/arm/armv7m.c (revision 534f6ff9)
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 
15 /* Bitbanded IO.  Each word corresponds to a single bit.  */
16 
17 /* Get the byte address of the real memory for a bitband access.  */
18 static inline uint32_t bitband_addr(void * opaque, uint32_t addr)
19 {
20     uint32_t res;
21 
22     res = *(uint32_t *)opaque;
23     res |= (addr & 0x1ffffff) >> 5;
24     return res;
25 
26 }
27 
28 static uint32_t bitband_readb(void *opaque, hwaddr offset)
29 {
30     uint8_t v;
31     cpu_physical_memory_read(bitband_addr(opaque, offset), &v, 1);
32     return (v & (1 << ((offset >> 2) & 7))) != 0;
33 }
34 
35 static void bitband_writeb(void *opaque, hwaddr offset,
36                            uint32_t value)
37 {
38     uint32_t addr;
39     uint8_t mask;
40     uint8_t v;
41     addr = bitband_addr(opaque, offset);
42     mask = (1 << ((offset >> 2) & 7));
43     cpu_physical_memory_read(addr, &v, 1);
44     if (value & 1)
45         v |= mask;
46     else
47         v &= ~mask;
48     cpu_physical_memory_write(addr, &v, 1);
49 }
50 
51 static uint32_t bitband_readw(void *opaque, hwaddr offset)
52 {
53     uint32_t addr;
54     uint16_t mask;
55     uint16_t v;
56     addr = bitband_addr(opaque, offset) & ~1;
57     mask = (1 << ((offset >> 2) & 15));
58     mask = tswap16(mask);
59     cpu_physical_memory_read(addr, &v, 2);
60     return (v & mask) != 0;
61 }
62 
63 static void bitband_writew(void *opaque, hwaddr offset,
64                            uint32_t value)
65 {
66     uint32_t addr;
67     uint16_t mask;
68     uint16_t v;
69     addr = bitband_addr(opaque, offset) & ~1;
70     mask = (1 << ((offset >> 2) & 15));
71     mask = tswap16(mask);
72     cpu_physical_memory_read(addr, &v, 2);
73     if (value & 1)
74         v |= mask;
75     else
76         v &= ~mask;
77     cpu_physical_memory_write(addr, &v, 2);
78 }
79 
80 static uint32_t bitband_readl(void *opaque, hwaddr offset)
81 {
82     uint32_t addr;
83     uint32_t mask;
84     uint32_t v;
85     addr = bitband_addr(opaque, offset) & ~3;
86     mask = (1 << ((offset >> 2) & 31));
87     mask = tswap32(mask);
88     cpu_physical_memory_read(addr, &v, 4);
89     return (v & mask) != 0;
90 }
91 
92 static void bitband_writel(void *opaque, hwaddr offset,
93                            uint32_t value)
94 {
95     uint32_t addr;
96     uint32_t mask;
97     uint32_t v;
98     addr = bitband_addr(opaque, offset) & ~3;
99     mask = (1 << ((offset >> 2) & 31));
100     mask = tswap32(mask);
101     cpu_physical_memory_read(addr, &v, 4);
102     if (value & 1)
103         v |= mask;
104     else
105         v &= ~mask;
106     cpu_physical_memory_write(addr, &v, 4);
107 }
108 
109 static const MemoryRegionOps bitband_ops = {
110     .old_mmio = {
111         .read = { bitband_readb, bitband_readw, bitband_readl, },
112         .write = { bitband_writeb, bitband_writew, bitband_writel, },
113     },
114     .endianness = DEVICE_NATIVE_ENDIAN,
115 };
116 
117 #define TYPE_BITBAND "ARM,bitband-memory"
118 #define BITBAND(obj) OBJECT_CHECK(BitBandState, (obj), TYPE_BITBAND)
119 
120 typedef struct {
121     /*< private >*/
122     SysBusDevice parent_obj;
123     /*< public >*/
124 
125     MemoryRegion iomem;
126     uint32_t base;
127 } BitBandState;
128 
129 static int bitband_init(SysBusDevice *dev)
130 {
131     BitBandState *s = BITBAND(dev);
132 
133     memory_region_init_io(&s->iomem, OBJECT(s), &bitband_ops, &s->base,
134                           "bitband", 0x02000000);
135     sysbus_init_mmio(dev, &s->iomem);
136     return 0;
137 }
138 
139 static void armv7m_bitband_init(void)
140 {
141     DeviceState *dev;
142 
143     dev = qdev_create(NULL, TYPE_BITBAND);
144     qdev_prop_set_uint32(dev, "base", 0x20000000);
145     qdev_init_nofail(dev);
146     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 0x22000000);
147 
148     dev = qdev_create(NULL, TYPE_BITBAND);
149     qdev_prop_set_uint32(dev, "base", 0x40000000);
150     qdev_init_nofail(dev);
151     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 0x42000000);
152 }
153 
154 /* Board init.  */
155 
156 static void armv7m_reset(void *opaque)
157 {
158     ARMCPU *cpu = opaque;
159 
160     cpu_reset(CPU(cpu));
161 }
162 
163 /* Init CPU and memory for a v7-M based board.
164    flash_size and sram_size are in kb.
165    Returns the NVIC array.  */
166 
167 qemu_irq *armv7m_init(MemoryRegion *address_space_mem,
168                       int flash_size, int sram_size,
169                       const char *kernel_filename, const char *cpu_model)
170 {
171     ARMCPU *cpu;
172     CPUARMState *env;
173     DeviceState *nvic;
174     /* FIXME: make this local state.  */
175     static qemu_irq pic[64];
176     qemu_irq *cpu_pic;
177     int image_size;
178     uint64_t entry;
179     uint64_t lowaddr;
180     int i;
181     int big_endian;
182     MemoryRegion *sram = g_new(MemoryRegion, 1);
183     MemoryRegion *flash = g_new(MemoryRegion, 1);
184     MemoryRegion *hack = g_new(MemoryRegion, 1);
185 
186     flash_size *= 1024;
187     sram_size *= 1024;
188 
189     if (cpu_model == NULL) {
190 	cpu_model = "cortex-m3";
191     }
192     cpu = cpu_arm_init(cpu_model);
193     if (cpu == NULL) {
194         fprintf(stderr, "Unable to find CPU definition\n");
195         exit(1);
196     }
197     env = &cpu->env;
198 
199 #if 0
200     /* > 32Mb SRAM gets complicated because it overlaps the bitband area.
201        We don't have proper commandline options, so allocate half of memory
202        as SRAM, up to a maximum of 32Mb, and the rest as code.  */
203     if (ram_size > (512 + 32) * 1024 * 1024)
204         ram_size = (512 + 32) * 1024 * 1024;
205     sram_size = (ram_size / 2) & TARGET_PAGE_MASK;
206     if (sram_size > 32 * 1024 * 1024)
207         sram_size = 32 * 1024 * 1024;
208     code_size = ram_size - sram_size;
209 #endif
210 
211     /* Flash programming is done via the SCU, so pretend it is ROM.  */
212     memory_region_init_ram(flash, NULL, "armv7m.flash", flash_size);
213     vmstate_register_ram_global(flash);
214     memory_region_set_readonly(flash, true);
215     memory_region_add_subregion(address_space_mem, 0, flash);
216     memory_region_init_ram(sram, NULL, "armv7m.sram", sram_size);
217     vmstate_register_ram_global(sram);
218     memory_region_add_subregion(address_space_mem, 0x20000000, sram);
219     armv7m_bitband_init();
220 
221     nvic = qdev_create(NULL, "armv7m_nvic");
222     env->nvic = nvic;
223     qdev_init_nofail(nvic);
224     cpu_pic = arm_pic_init_cpu(cpu);
225     sysbus_connect_irq(SYS_BUS_DEVICE(nvic), 0, cpu_pic[ARM_PIC_CPU_IRQ]);
226     for (i = 0; i < 64; i++) {
227         pic[i] = qdev_get_gpio_in(nvic, i);
228     }
229 
230 #ifdef TARGET_WORDS_BIGENDIAN
231     big_endian = 1;
232 #else
233     big_endian = 0;
234 #endif
235 
236     if (!kernel_filename) {
237         fprintf(stderr, "Guest image must be specified (using -kernel)\n");
238         exit(1);
239     }
240 
241     image_size = load_elf(kernel_filename, NULL, NULL, &entry, &lowaddr,
242                           NULL, big_endian, ELF_MACHINE, 1);
243     if (image_size < 0) {
244         image_size = load_image_targphys(kernel_filename, 0, flash_size);
245 	lowaddr = 0;
246     }
247     if (image_size < 0) {
248         fprintf(stderr, "qemu: could not load kernel '%s'\n",
249                 kernel_filename);
250         exit(1);
251     }
252 
253     /* Hack to map an additional page of ram at the top of the address
254        space.  This stops qemu complaining about executing code outside RAM
255        when returning from an exception.  */
256     memory_region_init_ram(hack, NULL, "armv7m.hack", 0x1000);
257     vmstate_register_ram_global(hack);
258     memory_region_add_subregion(address_space_mem, 0xfffff000, hack);
259 
260     qemu_register_reset(armv7m_reset, cpu);
261     return pic;
262 }
263 
264 static Property bitband_properties[] = {
265     DEFINE_PROP_UINT32("base", BitBandState, base, 0),
266     DEFINE_PROP_END_OF_LIST(),
267 };
268 
269 static void bitband_class_init(ObjectClass *klass, void *data)
270 {
271     DeviceClass *dc = DEVICE_CLASS(klass);
272     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
273 
274     k->init = bitband_init;
275     dc->props = bitband_properties;
276 }
277 
278 static const TypeInfo bitband_info = {
279     .name          = TYPE_BITBAND,
280     .parent        = TYPE_SYS_BUS_DEVICE,
281     .instance_size = sizeof(BitBandState),
282     .class_init    = bitband_class_init,
283 };
284 
285 static void armv7m_register_types(void)
286 {
287     type_register_static(&bitband_info);
288 }
289 
290 type_init(armv7m_register_types)
291