xref: /openbmc/qemu/hw/dma/sparc32_dma.c (revision 9884abee)
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 "qemu/osdep.h"
29 #include "hw/hw.h"
30 #include "hw/sparc/sparc32_dma.h"
31 #include "hw/sparc/sun4m.h"
32 #include "hw/sysbus.h"
33 #include "trace.h"
34 
35 /*
36  * This is the DMA controller part of chip STP2000 (Master I/O), also
37  * produced as NCR89C100. See
38  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C100.txt
39  * and
40  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/DMA2.txt
41  */
42 
43 #define DMA_REGS 4
44 #define DMA_SIZE (4 * sizeof(uint32_t))
45 /* We need the mask, because one instance of the device is not page
46    aligned (ledma, start address 0x0010) */
47 #define DMA_MASK (DMA_SIZE - 1)
48 /* OBP says 0x20 bytes for ledma, the extras are aliased to espdma */
49 #define DMA_ETH_SIZE (8 * sizeof(uint32_t))
50 #define DMA_MAX_REG_OFFSET (2 * DMA_SIZE - 1)
51 
52 #define DMA_VER 0xa0000000
53 #define DMA_INTR 1
54 #define DMA_INTREN 0x10
55 #define DMA_WRITE_MEM 0x100
56 #define DMA_EN 0x200
57 #define DMA_LOADED 0x04000000
58 #define DMA_DRAIN_FIFO 0x40
59 #define DMA_RESET 0x80
60 
61 /* XXX SCSI and ethernet should have different read-only bit masks */
62 #define DMA_CSR_RO_MASK 0xfe000007
63 
64 #define TYPE_SPARC32_DMA "sparc32_dma"
65 #define SPARC32_DMA(obj) OBJECT_CHECK(DMAState, (obj), TYPE_SPARC32_DMA)
66 
67 typedef struct DMAState DMAState;
68 
69 struct DMAState {
70     SysBusDevice parent_obj;
71 
72     MemoryRegion iomem;
73     uint32_t dmaregs[DMA_REGS];
74     qemu_irq irq;
75     void *iommu;
76     qemu_irq gpio[2];
77     uint32_t is_ledma;
78 };
79 
80 enum {
81     GPIO_RESET = 0,
82     GPIO_DMA,
83 };
84 
85 /* Note: on sparc, the lance 16 bit bus is swapped */
86 void ledma_memory_read(void *opaque, hwaddr addr,
87                        uint8_t *buf, int len, int do_bswap)
88 {
89     DMAState *s = opaque;
90     int i;
91 
92     addr |= s->dmaregs[3];
93     trace_ledma_memory_read(addr);
94     if (do_bswap) {
95         sparc_iommu_memory_read(s->iommu, addr, buf, len);
96     } else {
97         addr &= ~1;
98         len &= ~1;
99         sparc_iommu_memory_read(s->iommu, addr, buf, len);
100         for(i = 0; i < len; i += 2) {
101             bswap16s((uint16_t *)(buf + i));
102         }
103     }
104 }
105 
106 void ledma_memory_write(void *opaque, hwaddr addr,
107                         uint8_t *buf, int len, int do_bswap)
108 {
109     DMAState *s = opaque;
110     int l, i;
111     uint16_t tmp_buf[32];
112 
113     addr |= s->dmaregs[3];
114     trace_ledma_memory_write(addr);
115     if (do_bswap) {
116         sparc_iommu_memory_write(s->iommu, addr, buf, len);
117     } else {
118         addr &= ~1;
119         len &= ~1;
120         while (len > 0) {
121             l = len;
122             if (l > sizeof(tmp_buf))
123                 l = sizeof(tmp_buf);
124             for(i = 0; i < l; i += 2) {
125                 tmp_buf[i >> 1] = bswap16(*(uint16_t *)(buf + i));
126             }
127             sparc_iommu_memory_write(s->iommu, addr, (uint8_t *)tmp_buf, l);
128             len -= l;
129             buf += l;
130             addr += l;
131         }
132     }
133 }
134 
135 static void dma_set_irq(void *opaque, int irq, int level)
136 {
137     DMAState *s = opaque;
138     if (level) {
139         s->dmaregs[0] |= DMA_INTR;
140         if (s->dmaregs[0] & DMA_INTREN) {
141             trace_sparc32_dma_set_irq_raise();
142             qemu_irq_raise(s->irq);
143         }
144     } else {
145         if (s->dmaregs[0] & DMA_INTR) {
146             s->dmaregs[0] &= ~DMA_INTR;
147             if (s->dmaregs[0] & DMA_INTREN) {
148                 trace_sparc32_dma_set_irq_lower();
149                 qemu_irq_lower(s->irq);
150             }
151         }
152     }
153 }
154 
155 void espdma_memory_read(void *opaque, uint8_t *buf, int len)
156 {
157     DMAState *s = opaque;
158 
159     trace_espdma_memory_read(s->dmaregs[1]);
160     sparc_iommu_memory_read(s->iommu, s->dmaregs[1], buf, len);
161     s->dmaregs[1] += len;
162 }
163 
164 void espdma_memory_write(void *opaque, uint8_t *buf, int len)
165 {
166     DMAState *s = opaque;
167 
168     trace_espdma_memory_write(s->dmaregs[1]);
169     sparc_iommu_memory_write(s->iommu, s->dmaregs[1], buf, len);
170     s->dmaregs[1] += len;
171 }
172 
173 static uint64_t dma_mem_read(void *opaque, hwaddr addr,
174                              unsigned size)
175 {
176     DMAState *s = opaque;
177     uint32_t saddr;
178 
179     if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
180         /* aliased to espdma, but we can't get there from here */
181         /* buggy driver if using undocumented behavior, just return 0 */
182         trace_sparc32_dma_mem_readl(addr, 0);
183         return 0;
184     }
185     saddr = (addr & DMA_MASK) >> 2;
186     trace_sparc32_dma_mem_readl(addr, s->dmaregs[saddr]);
187     return s->dmaregs[saddr];
188 }
189 
190 static void dma_mem_write(void *opaque, hwaddr addr,
191                           uint64_t val, unsigned size)
192 {
193     DMAState *s = opaque;
194     uint32_t saddr;
195 
196     if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
197         /* aliased to espdma, but we can't get there from here */
198         trace_sparc32_dma_mem_writel(addr, 0, val);
199         return;
200     }
201     saddr = (addr & DMA_MASK) >> 2;
202     trace_sparc32_dma_mem_writel(addr, s->dmaregs[saddr], val);
203     switch (saddr) {
204     case 0:
205         if (val & DMA_INTREN) {
206             if (s->dmaregs[0] & DMA_INTR) {
207                 trace_sparc32_dma_set_irq_raise();
208                 qemu_irq_raise(s->irq);
209             }
210         } else {
211             if (s->dmaregs[0] & (DMA_INTR | DMA_INTREN)) {
212                 trace_sparc32_dma_set_irq_lower();
213                 qemu_irq_lower(s->irq);
214             }
215         }
216         if (val & DMA_RESET) {
217             qemu_irq_raise(s->gpio[GPIO_RESET]);
218             qemu_irq_lower(s->gpio[GPIO_RESET]);
219         } else if (val & DMA_DRAIN_FIFO) {
220             val &= ~DMA_DRAIN_FIFO;
221         } else if (val == 0)
222             val = DMA_DRAIN_FIFO;
223 
224         if (val & DMA_EN && !(s->dmaregs[0] & DMA_EN)) {
225             trace_sparc32_dma_enable_raise();
226             qemu_irq_raise(s->gpio[GPIO_DMA]);
227         } else if (!(val & DMA_EN) && !!(s->dmaregs[0] & DMA_EN)) {
228             trace_sparc32_dma_enable_lower();
229             qemu_irq_lower(s->gpio[GPIO_DMA]);
230         }
231 
232         val &= ~DMA_CSR_RO_MASK;
233         val |= DMA_VER;
234         s->dmaregs[0] = (s->dmaregs[0] & DMA_CSR_RO_MASK) | val;
235         break;
236     case 1:
237         s->dmaregs[0] |= DMA_LOADED;
238         /* fall through */
239     default:
240         s->dmaregs[saddr] = val;
241         break;
242     }
243 }
244 
245 static const MemoryRegionOps dma_mem_ops = {
246     .read = dma_mem_read,
247     .write = dma_mem_write,
248     .endianness = DEVICE_NATIVE_ENDIAN,
249     .valid = {
250         .min_access_size = 4,
251         .max_access_size = 4,
252     },
253 };
254 
255 static void dma_reset(DeviceState *d)
256 {
257     DMAState *s = SPARC32_DMA(d);
258 
259     memset(s->dmaregs, 0, DMA_SIZE);
260     s->dmaregs[0] = DMA_VER;
261 }
262 
263 static const VMStateDescription vmstate_dma = {
264     .name ="sparc32_dma",
265     .version_id = 2,
266     .minimum_version_id = 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