xref: /openbmc/qemu/hw/dma/sparc32_dma.c (revision b2c623a3)
1 /*
2  * QEMU Sparc32 DMA controller emulation
3  *
4  * Copyright (c) 2006 Fabrice Bellard
5  *
6  * Modifications:
7  *  2010-Feb-14 Artyom Tarasenko : reworked irq generation
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a copy
10  * of this software and associated documentation files (the "Software"), to deal
11  * in the Software without restriction, including without limitation the rights
12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13  * copies of the Software, and to permit persons to whom the Software is
14  * furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25  * THE SOFTWARE.
26  */
27 
28 #include "hw/hw.h"
29 #include "hw/sparc/sparc32_dma.h"
30 #include "hw/sparc/sun4m.h"
31 #include "hw/sysbus.h"
32 #include "trace.h"
33 
34 /*
35  * This is the DMA controller part of chip STP2000 (Master I/O), also
36  * produced as NCR89C100. See
37  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C100.txt
38  * and
39  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/DMA2.txt
40  */
41 
42 #define DMA_REGS 4
43 #define DMA_SIZE (4 * sizeof(uint32_t))
44 /* We need the mask, because one instance of the device is not page
45    aligned (ledma, start address 0x0010) */
46 #define DMA_MASK (DMA_SIZE - 1)
47 /* OBP says 0x20 bytes for ledma, the extras are aliased to espdma */
48 #define DMA_ETH_SIZE (8 * sizeof(uint32_t))
49 #define DMA_MAX_REG_OFFSET (2 * DMA_SIZE - 1)
50 
51 #define DMA_VER 0xa0000000
52 #define DMA_INTR 1
53 #define DMA_INTREN 0x10
54 #define DMA_WRITE_MEM 0x100
55 #define DMA_EN 0x200
56 #define DMA_LOADED 0x04000000
57 #define DMA_DRAIN_FIFO 0x40
58 #define DMA_RESET 0x80
59 
60 /* XXX SCSI and ethernet should have different read-only bit masks */
61 #define DMA_CSR_RO_MASK 0xfe000007
62 
63 #define TYPE_SPARC32_DMA "sparc32_dma"
64 #define SPARC32_DMA(obj) OBJECT_CHECK(DMAState, (obj), TYPE_SPARC32_DMA)
65 
66 typedef struct DMAState DMAState;
67 
68 struct DMAState {
69     SysBusDevice parent_obj;
70 
71     MemoryRegion iomem;
72     uint32_t dmaregs[DMA_REGS];
73     qemu_irq irq;
74     void *iommu;
75     qemu_irq gpio[2];
76     uint32_t is_ledma;
77 };
78 
79 enum {
80     GPIO_RESET = 0,
81     GPIO_DMA,
82 };
83 
84 /* Note: on sparc, the lance 16 bit bus is swapped */
85 void ledma_memory_read(void *opaque, hwaddr addr,
86                        uint8_t *buf, int len, int do_bswap)
87 {
88     DMAState *s = opaque;
89     int i;
90 
91     addr |= s->dmaregs[3];
92     trace_ledma_memory_read(addr);
93     if (do_bswap) {
94         sparc_iommu_memory_read(s->iommu, addr, buf, len);
95     } else {
96         addr &= ~1;
97         len &= ~1;
98         sparc_iommu_memory_read(s->iommu, addr, buf, len);
99         for(i = 0; i < len; i += 2) {
100             bswap16s((uint16_t *)(buf + i));
101         }
102     }
103 }
104 
105 void ledma_memory_write(void *opaque, hwaddr addr,
106                         uint8_t *buf, int len, int do_bswap)
107 {
108     DMAState *s = opaque;
109     int l, i;
110     uint16_t tmp_buf[32];
111 
112     addr |= s->dmaregs[3];
113     trace_ledma_memory_write(addr);
114     if (do_bswap) {
115         sparc_iommu_memory_write(s->iommu, addr, buf, len);
116     } else {
117         addr &= ~1;
118         len &= ~1;
119         while (len > 0) {
120             l = len;
121             if (l > sizeof(tmp_buf))
122                 l = sizeof(tmp_buf);
123             for(i = 0; i < l; i += 2) {
124                 tmp_buf[i >> 1] = bswap16(*(uint16_t *)(buf + i));
125             }
126             sparc_iommu_memory_write(s->iommu, addr, (uint8_t *)tmp_buf, l);
127             len -= l;
128             buf += l;
129             addr += l;
130         }
131     }
132 }
133 
134 static void dma_set_irq(void *opaque, int irq, int level)
135 {
136     DMAState *s = opaque;
137     if (level) {
138         s->dmaregs[0] |= DMA_INTR;
139         if (s->dmaregs[0] & DMA_INTREN) {
140             trace_sparc32_dma_set_irq_raise();
141             qemu_irq_raise(s->irq);
142         }
143     } else {
144         if (s->dmaregs[0] & DMA_INTR) {
145             s->dmaregs[0] &= ~DMA_INTR;
146             if (s->dmaregs[0] & DMA_INTREN) {
147                 trace_sparc32_dma_set_irq_lower();
148                 qemu_irq_lower(s->irq);
149             }
150         }
151     }
152 }
153 
154 void espdma_memory_read(void *opaque, uint8_t *buf, int len)
155 {
156     DMAState *s = opaque;
157 
158     trace_espdma_memory_read(s->dmaregs[1]);
159     sparc_iommu_memory_read(s->iommu, s->dmaregs[1], buf, len);
160     s->dmaregs[1] += len;
161 }
162 
163 void espdma_memory_write(void *opaque, uint8_t *buf, int len)
164 {
165     DMAState *s = opaque;
166 
167     trace_espdma_memory_write(s->dmaregs[1]);
168     sparc_iommu_memory_write(s->iommu, s->dmaregs[1], buf, len);
169     s->dmaregs[1] += len;
170 }
171 
172 static uint64_t dma_mem_read(void *opaque, hwaddr addr,
173                              unsigned size)
174 {
175     DMAState *s = opaque;
176     uint32_t saddr;
177 
178     if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
179         /* aliased to espdma, but we can't get there from here */
180         /* buggy driver if using undocumented behavior, just return 0 */
181         trace_sparc32_dma_mem_readl(addr, 0);
182         return 0;
183     }
184     saddr = (addr & DMA_MASK) >> 2;
185     trace_sparc32_dma_mem_readl(addr, s->dmaregs[saddr]);
186     return s->dmaregs[saddr];
187 }
188 
189 static void dma_mem_write(void *opaque, hwaddr addr,
190                           uint64_t val, unsigned size)
191 {
192     DMAState *s = opaque;
193     uint32_t saddr;
194 
195     if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
196         /* aliased to espdma, but we can't get there from here */
197         trace_sparc32_dma_mem_writel(addr, 0, val);
198         return;
199     }
200     saddr = (addr & DMA_MASK) >> 2;
201     trace_sparc32_dma_mem_writel(addr, s->dmaregs[saddr], val);
202     switch (saddr) {
203     case 0:
204         if (val & DMA_INTREN) {
205             if (s->dmaregs[0] & DMA_INTR) {
206                 trace_sparc32_dma_set_irq_raise();
207                 qemu_irq_raise(s->irq);
208             }
209         } else {
210             if (s->dmaregs[0] & (DMA_INTR | DMA_INTREN)) {
211                 trace_sparc32_dma_set_irq_lower();
212                 qemu_irq_lower(s->irq);
213             }
214         }
215         if (val & DMA_RESET) {
216             qemu_irq_raise(s->gpio[GPIO_RESET]);
217             qemu_irq_lower(s->gpio[GPIO_RESET]);
218         } else if (val & DMA_DRAIN_FIFO) {
219             val &= ~DMA_DRAIN_FIFO;
220         } else if (val == 0)
221             val = DMA_DRAIN_FIFO;
222 
223         if (val & DMA_EN && !(s->dmaregs[0] & DMA_EN)) {
224             trace_sparc32_dma_enable_raise();
225             qemu_irq_raise(s->gpio[GPIO_DMA]);
226         } else if (!(val & DMA_EN) && !!(s->dmaregs[0] & DMA_EN)) {
227             trace_sparc32_dma_enable_lower();
228             qemu_irq_lower(s->gpio[GPIO_DMA]);
229         }
230 
231         val &= ~DMA_CSR_RO_MASK;
232         val |= DMA_VER;
233         s->dmaregs[0] = (s->dmaregs[0] & DMA_CSR_RO_MASK) | val;
234         break;
235     case 1:
236         s->dmaregs[0] |= DMA_LOADED;
237         /* fall through */
238     default:
239         s->dmaregs[saddr] = val;
240         break;
241     }
242 }
243 
244 static const MemoryRegionOps dma_mem_ops = {
245     .read = dma_mem_read,
246     .write = dma_mem_write,
247     .endianness = DEVICE_NATIVE_ENDIAN,
248     .valid = {
249         .min_access_size = 4,
250         .max_access_size = 4,
251     },
252 };
253 
254 static void dma_reset(DeviceState *d)
255 {
256     DMAState *s = SPARC32_DMA(d);
257 
258     memset(s->dmaregs, 0, DMA_SIZE);
259     s->dmaregs[0] = DMA_VER;
260 }
261 
262 static const VMStateDescription vmstate_dma = {
263     .name ="sparc32_dma",
264     .version_id = 2,
265     .minimum_version_id = 2,
266     .minimum_version_id_old = 2,
267     .fields      = (VMStateField []) {
268         VMSTATE_UINT32_ARRAY(dmaregs, DMAState, DMA_REGS),
269         VMSTATE_END_OF_LIST()
270     }
271 };
272 
273 static int sparc32_dma_init1(SysBusDevice *sbd)
274 {
275     DeviceState *dev = DEVICE(sbd);
276     DMAState *s = SPARC32_DMA(dev);
277     int reg_size;
278 
279     sysbus_init_irq(sbd, &s->irq);
280 
281     reg_size = s->is_ledma ? DMA_ETH_SIZE : DMA_SIZE;
282     memory_region_init_io(&s->iomem, OBJECT(s), &dma_mem_ops, s,
283                           "dma", reg_size);
284     sysbus_init_mmio(sbd, &s->iomem);
285 
286     qdev_init_gpio_in(dev, dma_set_irq, 1);
287     qdev_init_gpio_out(dev, s->gpio, 2);
288 
289     return 0;
290 }
291 
292 static Property sparc32_dma_properties[] = {
293     DEFINE_PROP_PTR("iommu_opaque", DMAState, iommu),
294     DEFINE_PROP_UINT32("is_ledma", DMAState, is_ledma, 0),
295     DEFINE_PROP_END_OF_LIST(),
296 };
297 
298 static void sparc32_dma_class_init(ObjectClass *klass, void *data)
299 {
300     DeviceClass *dc = DEVICE_CLASS(klass);
301     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
302 
303     k->init = sparc32_dma_init1;
304     dc->reset = dma_reset;
305     dc->vmsd = &vmstate_dma;
306     dc->props = sparc32_dma_properties;
307     /* Reason: pointer property "iommu_opaque" */
308     dc->cannot_instantiate_with_device_add_yet = true;
309 }
310 
311 static const TypeInfo sparc32_dma_info = {
312     .name          = TYPE_SPARC32_DMA,
313     .parent        = TYPE_SYS_BUS_DEVICE,
314     .instance_size = sizeof(DMAState),
315     .class_init    = sparc32_dma_class_init,
316 };
317 
318 static void sparc32_dma_register_types(void)
319 {
320     type_register_static(&sparc32_dma_info);
321 }
322 
323 type_init(sparc32_dma_register_types)
324