xref: /openbmc/qemu/hw/dma/sparc32_dma.c (revision 47b43a1f)
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 typedef struct DMAState DMAState;
64 
65 struct DMAState {
66     SysBusDevice busdev;
67     MemoryRegion iomem;
68     uint32_t dmaregs[DMA_REGS];
69     qemu_irq irq;
70     void *iommu;
71     qemu_irq gpio[2];
72     uint32_t is_ledma;
73 };
74 
75 enum {
76     GPIO_RESET = 0,
77     GPIO_DMA,
78 };
79 
80 /* Note: on sparc, the lance 16 bit bus is swapped */
81 void ledma_memory_read(void *opaque, hwaddr addr,
82                        uint8_t *buf, int len, int do_bswap)
83 {
84     DMAState *s = opaque;
85     int i;
86 
87     addr |= s->dmaregs[3];
88     trace_ledma_memory_read(addr);
89     if (do_bswap) {
90         sparc_iommu_memory_read(s->iommu, addr, buf, len);
91     } else {
92         addr &= ~1;
93         len &= ~1;
94         sparc_iommu_memory_read(s->iommu, addr, buf, len);
95         for(i = 0; i < len; i += 2) {
96             bswap16s((uint16_t *)(buf + i));
97         }
98     }
99 }
100 
101 void ledma_memory_write(void *opaque, hwaddr addr,
102                         uint8_t *buf, int len, int do_bswap)
103 {
104     DMAState *s = opaque;
105     int l, i;
106     uint16_t tmp_buf[32];
107 
108     addr |= s->dmaregs[3];
109     trace_ledma_memory_write(addr);
110     if (do_bswap) {
111         sparc_iommu_memory_write(s->iommu, addr, buf, len);
112     } else {
113         addr &= ~1;
114         len &= ~1;
115         while (len > 0) {
116             l = len;
117             if (l > sizeof(tmp_buf))
118                 l = sizeof(tmp_buf);
119             for(i = 0; i < l; i += 2) {
120                 tmp_buf[i >> 1] = bswap16(*(uint16_t *)(buf + i));
121             }
122             sparc_iommu_memory_write(s->iommu, addr, (uint8_t *)tmp_buf, l);
123             len -= l;
124             buf += l;
125             addr += l;
126         }
127     }
128 }
129 
130 static void dma_set_irq(void *opaque, int irq, int level)
131 {
132     DMAState *s = opaque;
133     if (level) {
134         s->dmaregs[0] |= DMA_INTR;
135         if (s->dmaregs[0] & DMA_INTREN) {
136             trace_sparc32_dma_set_irq_raise();
137             qemu_irq_raise(s->irq);
138         }
139     } else {
140         if (s->dmaregs[0] & DMA_INTR) {
141             s->dmaregs[0] &= ~DMA_INTR;
142             if (s->dmaregs[0] & DMA_INTREN) {
143                 trace_sparc32_dma_set_irq_lower();
144                 qemu_irq_lower(s->irq);
145             }
146         }
147     }
148 }
149 
150 void espdma_memory_read(void *opaque, uint8_t *buf, int len)
151 {
152     DMAState *s = opaque;
153 
154     trace_espdma_memory_read(s->dmaregs[1]);
155     sparc_iommu_memory_read(s->iommu, s->dmaregs[1], buf, len);
156     s->dmaregs[1] += len;
157 }
158 
159 void espdma_memory_write(void *opaque, uint8_t *buf, int len)
160 {
161     DMAState *s = opaque;
162 
163     trace_espdma_memory_write(s->dmaregs[1]);
164     sparc_iommu_memory_write(s->iommu, s->dmaregs[1], buf, len);
165     s->dmaregs[1] += len;
166 }
167 
168 static uint64_t dma_mem_read(void *opaque, hwaddr addr,
169                              unsigned size)
170 {
171     DMAState *s = opaque;
172     uint32_t saddr;
173 
174     if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
175         /* aliased to espdma, but we can't get there from here */
176         /* buggy driver if using undocumented behavior, just return 0 */
177         trace_sparc32_dma_mem_readl(addr, 0);
178         return 0;
179     }
180     saddr = (addr & DMA_MASK) >> 2;
181     trace_sparc32_dma_mem_readl(addr, s->dmaregs[saddr]);
182     return s->dmaregs[saddr];
183 }
184 
185 static void dma_mem_write(void *opaque, hwaddr addr,
186                           uint64_t val, unsigned size)
187 {
188     DMAState *s = opaque;
189     uint32_t saddr;
190 
191     if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
192         /* aliased to espdma, but we can't get there from here */
193         trace_sparc32_dma_mem_writel(addr, 0, val);
194         return;
195     }
196     saddr = (addr & DMA_MASK) >> 2;
197     trace_sparc32_dma_mem_writel(addr, s->dmaregs[saddr], val);
198     switch (saddr) {
199     case 0:
200         if (val & DMA_INTREN) {
201             if (s->dmaregs[0] & DMA_INTR) {
202                 trace_sparc32_dma_set_irq_raise();
203                 qemu_irq_raise(s->irq);
204             }
205         } else {
206             if (s->dmaregs[0] & (DMA_INTR | DMA_INTREN)) {
207                 trace_sparc32_dma_set_irq_lower();
208                 qemu_irq_lower(s->irq);
209             }
210         }
211         if (val & DMA_RESET) {
212             qemu_irq_raise(s->gpio[GPIO_RESET]);
213             qemu_irq_lower(s->gpio[GPIO_RESET]);
214         } else if (val & DMA_DRAIN_FIFO) {
215             val &= ~DMA_DRAIN_FIFO;
216         } else if (val == 0)
217             val = DMA_DRAIN_FIFO;
218 
219         if (val & DMA_EN && !(s->dmaregs[0] & DMA_EN)) {
220             trace_sparc32_dma_enable_raise();
221             qemu_irq_raise(s->gpio[GPIO_DMA]);
222         } else if (!(val & DMA_EN) && !!(s->dmaregs[0] & DMA_EN)) {
223             trace_sparc32_dma_enable_lower();
224             qemu_irq_lower(s->gpio[GPIO_DMA]);
225         }
226 
227         val &= ~DMA_CSR_RO_MASK;
228         val |= DMA_VER;
229         s->dmaregs[0] = (s->dmaregs[0] & DMA_CSR_RO_MASK) | val;
230         break;
231     case 1:
232         s->dmaregs[0] |= DMA_LOADED;
233         /* fall through */
234     default:
235         s->dmaregs[saddr] = val;
236         break;
237     }
238 }
239 
240 static const MemoryRegionOps dma_mem_ops = {
241     .read = dma_mem_read,
242     .write = dma_mem_write,
243     .endianness = DEVICE_NATIVE_ENDIAN,
244     .valid = {
245         .min_access_size = 4,
246         .max_access_size = 4,
247     },
248 };
249 
250 static void dma_reset(DeviceState *d)
251 {
252     DMAState *s = container_of(d, DMAState, busdev.qdev);
253 
254     memset(s->dmaregs, 0, DMA_SIZE);
255     s->dmaregs[0] = DMA_VER;
256 }
257 
258 static const VMStateDescription vmstate_dma = {
259     .name ="sparc32_dma",
260     .version_id = 2,
261     .minimum_version_id = 2,
262     .minimum_version_id_old = 2,
263     .fields      = (VMStateField []) {
264         VMSTATE_UINT32_ARRAY(dmaregs, DMAState, DMA_REGS),
265         VMSTATE_END_OF_LIST()
266     }
267 };
268 
269 static int sparc32_dma_init1(SysBusDevice *dev)
270 {
271     DMAState *s = FROM_SYSBUS(DMAState, dev);
272     int reg_size;
273 
274     sysbus_init_irq(dev, &s->irq);
275 
276     reg_size = s->is_ledma ? DMA_ETH_SIZE : DMA_SIZE;
277     memory_region_init_io(&s->iomem, &dma_mem_ops, s, "dma", reg_size);
278     sysbus_init_mmio(dev, &s->iomem);
279 
280     qdev_init_gpio_in(&dev->qdev, dma_set_irq, 1);
281     qdev_init_gpio_out(&dev->qdev, s->gpio, 2);
282 
283     return 0;
284 }
285 
286 static Property sparc32_dma_properties[] = {
287     DEFINE_PROP_PTR("iommu_opaque", DMAState, iommu),
288     DEFINE_PROP_UINT32("is_ledma", DMAState, is_ledma, 0),
289     DEFINE_PROP_END_OF_LIST(),
290 };
291 
292 static void sparc32_dma_class_init(ObjectClass *klass, void *data)
293 {
294     DeviceClass *dc = DEVICE_CLASS(klass);
295     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
296 
297     k->init = sparc32_dma_init1;
298     dc->reset = dma_reset;
299     dc->vmsd = &vmstate_dma;
300     dc->props = sparc32_dma_properties;
301 }
302 
303 static const TypeInfo sparc32_dma_info = {
304     .name          = "sparc32_dma",
305     .parent        = TYPE_SYS_BUS_DEVICE,
306     .instance_size = sizeof(DMAState),
307     .class_init    = sparc32_dma_class_init,
308 };
309 
310 static void sparc32_dma_register_types(void)
311 {
312     type_register_static(&sparc32_dma_info);
313 }
314 
315 type_init(sparc32_dma_register_types)
316