xref: /openbmc/qemu/hw/arm/armv7m.c (revision 886ce6f8)
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    mem_size is in bytes.
167    Returns the NVIC array.  */
168 
169 DeviceState *armv7m_init(MemoryRegion *system_memory, int mem_size, int num_irq,
170                       const char *kernel_filename, const char *cpu_model)
171 {
172     ARMCPU *cpu;
173     CPUARMState *env;
174     DeviceState *nvic;
175     int image_size;
176     uint64_t entry;
177     uint64_t lowaddr;
178     int big_endian;
179     MemoryRegion *hack = g_new(MemoryRegion, 1);
180 
181     if (cpu_model == NULL) {
182 	cpu_model = "cortex-m3";
183     }
184     cpu = cpu_arm_init(cpu_model);
185     if (cpu == NULL) {
186         fprintf(stderr, "Unable to find CPU definition\n");
187         exit(1);
188     }
189     env = &cpu->env;
190 
191     armv7m_bitband_init();
192 
193     nvic = qdev_create(NULL, "armv7m_nvic");
194     qdev_prop_set_uint32(nvic, "num-irq", num_irq);
195     env->nvic = nvic;
196     qdev_init_nofail(nvic);
197     sysbus_connect_irq(SYS_BUS_DEVICE(nvic), 0,
198                        qdev_get_gpio_in(DEVICE(cpu), ARM_CPU_IRQ));
199 
200 #ifdef TARGET_WORDS_BIGENDIAN
201     big_endian = 1;
202 #else
203     big_endian = 0;
204 #endif
205 
206     if (!kernel_filename && !qtest_enabled()) {
207         fprintf(stderr, "Guest image must be specified (using -kernel)\n");
208         exit(1);
209     }
210 
211     if (kernel_filename) {
212         image_size = load_elf(kernel_filename, NULL, NULL, &entry, &lowaddr,
213                               NULL, big_endian, EM_ARM, 1);
214         if (image_size < 0) {
215             image_size = load_image_targphys(kernel_filename, 0, mem_size);
216             lowaddr = 0;
217         }
218         if (image_size < 0) {
219             error_report("Could not load kernel '%s'", kernel_filename);
220             exit(1);
221         }
222     }
223 
224     /* Hack to map an additional page of ram at the top of the address
225        space.  This stops qemu complaining about executing code outside RAM
226        when returning from an exception.  */
227     memory_region_init_ram(hack, NULL, "armv7m.hack", 0x1000, &error_fatal);
228     vmstate_register_ram_global(hack);
229     memory_region_add_subregion(system_memory, 0xfffff000, hack);
230 
231     qemu_register_reset(armv7m_reset, cpu);
232     return nvic;
233 }
234 
235 static Property bitband_properties[] = {
236     DEFINE_PROP_UINT32("base", BitBandState, base, 0),
237     DEFINE_PROP_END_OF_LIST(),
238 };
239 
240 static void bitband_class_init(ObjectClass *klass, void *data)
241 {
242     DeviceClass *dc = DEVICE_CLASS(klass);
243     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
244 
245     k->init = bitband_init;
246     dc->props = bitband_properties;
247 }
248 
249 static const TypeInfo bitband_info = {
250     .name          = TYPE_BITBAND,
251     .parent        = TYPE_SYS_BUS_DEVICE,
252     .instance_size = sizeof(BitBandState),
253     .class_init    = bitband_class_init,
254 };
255 
256 static void armv7m_register_types(void)
257 {
258     type_register_static(&bitband_info);
259 }
260 
261 type_init(armv7m_register_types)
262