framebuffer.cpp revision cdb66fbc8a192e4b01b8b529c78773b2a3bf4573 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <sys/mman.h>
18
19#include <dlfcn.h>
20
21#include <cutils/ashmem.h>
22#include <cutils/log.h>
23
24#include <hardware/hardware.h>
25#include <hardware/gralloc.h>
26
27#include <fcntl.h>
28#include <errno.h>
29
30#include <cutils/log.h>
31#include <cutils/atomic.h>
32
33#if HAVE_ANDROID_OS
34#include <linux/fb.h>
35#endif
36
37#include "gralloc_priv.h"
38
39/*****************************************************************************/
40
41// should be a build option
42#define SUPPORTS_UPDATE_ON_DEMAND   1
43
44// fb_fix_screeninfo::id returned on the emulator
45#define EMULATOR_DEV_FB_ID ""
46
47// numbers of buffers for page flipping
48#define NUM_BUFFERS 2
49
50
51enum {
52    PAGE_FLIP = 0x00000001,
53    LOCKED = 0x00000002
54};
55
56struct fb_context_t {
57    framebuffer_device_t  device;
58};
59
60/*****************************************************************************/
61
62static int fb_setSwapInterval(struct framebuffer_device_t* dev,
63            int interval)
64{
65    fb_context_t* ctx = (fb_context_t*)dev;
66    if (interval < dev->minSwapInterval || interval > dev->maxSwapInterval)
67        return -EINVAL;
68    // FIXME: implement fb_setSwapInterval
69    return 0;
70}
71
72static int fb_setUpdateRect(struct framebuffer_device_t* dev,
73        int l, int t, int w, int h)
74{
75    if (((w|h) <= 0) || ((l|t)<0))
76        return -EINVAL;
77
78    fb_context_t* ctx = (fb_context_t*)dev;
79    private_module_t* m = reinterpret_cast<private_module_t*>(
80            dev->common.module);
81    m->info.reserved[0] = 0x54445055; // "UPDT";
82    m->info.reserved[1] = (uint16_t)l | ((uint32_t)t << 16);
83    m->info.reserved[2] = (uint16_t)(l+w) | ((uint32_t)(t+h) << 16);
84    return 0;
85}
86
87static int fb_post(struct framebuffer_device_t* dev, buffer_handle_t buffer)
88{
89    if (private_handle_t::validate(buffer) < 0)
90        return -EINVAL;
91
92    fb_context_t* ctx = (fb_context_t*)dev;
93
94    private_handle_t const* hnd = reinterpret_cast<private_handle_t const*>(buffer);
95    private_module_t* m = reinterpret_cast<private_module_t*>(
96            dev->common.module);
97
98    if (m->currentBuffer) {
99        m->base.unlock(&m->base, m->currentBuffer);
100        m->currentBuffer = 0;
101    }
102
103    if (hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER) {
104
105        m->base.lock(&m->base, buffer,
106                private_module_t::PRIV_USAGE_LOCKED_FOR_POST,
107                0, 0, m->info.xres, m->info.yres, NULL);
108
109        const size_t offset = hnd->base - m->framebuffer->base;
110        m->info.activate = FB_ACTIVATE_VBL;
111        m->info.yoffset = offset / m->finfo.line_length;
112        if (ioctl(m->framebuffer->fd, FBIOPUT_VSCREENINFO, &m->info) == -1) {
113            LOGE("FBIOPUT_VSCREENINFO failed");
114            m->base.unlock(&m->base, buffer);
115            return -errno;
116        }
117        m->currentBuffer = buffer;
118
119    } else {
120        // If we can't do the page_flip, just copy the buffer to the front
121        // FIXME: use copybit HAL instead of memcpy
122
123        void* fb_vaddr;
124        void* buffer_vaddr;
125
126        m->base.lock(&m->base, m->framebuffer,
127                GRALLOC_USAGE_SW_WRITE_RARELY,
128                0, 0, m->info.xres, m->info.yres,
129                &fb_vaddr);
130
131        m->base.lock(&m->base, buffer,
132                GRALLOC_USAGE_SW_READ_RARELY,
133                0, 0, m->info.xres, m->info.yres,
134                &buffer_vaddr);
135
136        memcpy(fb_vaddr, buffer_vaddr, m->finfo.line_length * m->info.yres);
137
138        m->base.unlock(&m->base, buffer);
139        m->base.unlock(&m->base, m->framebuffer);
140    }
141
142    return 0;
143}
144
145/*****************************************************************************/
146
147int mapFrameBufferLocked(struct private_module_t* module)
148{
149    // already initialized...
150    if (module->framebuffer) {
151        return 0;
152    }
153
154    char const * const device_template[] = {
155            "/dev/graphics/fb%u",
156            "/dev/fb%u",
157            0 };
158
159    int fd = -1;
160    int i=0;
161    char name[64];
162
163    while ((fd==-1) && device_template[i]) {
164        snprintf(name, 64, device_template[i], 0);
165        fd = open(name, O_RDWR, 0);
166        i++;
167    }
168    if (fd < 0)
169        return -errno;
170
171    struct fb_fix_screeninfo finfo;
172    if (ioctl(fd, FBIOGET_FSCREENINFO, &finfo) == -1)
173        return -errno;
174
175    struct fb_var_screeninfo info;
176    if (ioctl(fd, FBIOGET_VSCREENINFO, &info) == -1)
177        return -errno;
178
179    info.reserved[0] = 0;
180    info.reserved[1] = 0;
181    info.reserved[2] = 0;
182    info.xoffset = 0;
183    info.yoffset = 0;
184    info.activate = FB_ACTIVATE_NOW;
185
186    /*
187     * Explicitly request 5/6/5
188     */
189    info.bits_per_pixel = 16;
190    info.red.offset     = 11;
191    info.red.length     = 5;
192    info.green.offset   = 5;
193    info.green.length   = 6;
194    info.blue.offset    = 0;
195    info.blue.length    = 5;
196    info.transp.offset  = 0;
197    info.transp.length  = 0;
198
199    /*
200     * Request NUM_BUFFERS screens (at lest 2 for page flipping)
201     */
202    info.yres_virtual = info.yres * NUM_BUFFERS;
203
204
205    uint32_t flags = PAGE_FLIP;
206    if (ioctl(fd, FBIOPUT_VSCREENINFO, &info) == -1) {
207        info.yres_virtual = info.yres;
208        flags &= ~PAGE_FLIP;
209        LOGW("FBIOPUT_VSCREENINFO failed, page flipping not supported");
210    }
211
212    if (info.yres_virtual < info.yres * 2) {
213        // we need at least 2 for page-flipping
214        info.yres_virtual = info.yres;
215        flags &= ~PAGE_FLIP;
216        LOGW("page flipping not supported (yres_virtual=%d, requested=%d)",
217                info.yres_virtual, info.yres*2);
218    }
219
220    if (ioctl(fd, FBIOGET_VSCREENINFO, &info) == -1)
221        return -errno;
222
223    int refreshRate = 1000000000000000LLU /
224    (
225            uint64_t( info.upper_margin + info.lower_margin + info.yres )
226            * ( info.left_margin  + info.right_margin + info.xres )
227            * info.pixclock
228    );
229
230    if (refreshRate == 0) {
231        // bleagh, bad info from the driver
232        refreshRate = 60*1000;  // 60 Hz
233    }
234
235    if (int(info.width) <= 0 || int(info.height) <= 0) {
236        // the driver doesn't return that information
237        // default to 160 dpi
238        info.width  = ((info.xres * 25.4f)/160.0f + 0.5f);
239        info.height = ((info.yres * 25.4f)/160.0f + 0.5f);
240    }
241
242    float xdpi = (info.xres * 25.4f) / info.width;
243    float ydpi = (info.yres * 25.4f) / info.height;
244    float fps  = refreshRate / 1000.0f;
245
246    LOGI(   "using (fd=%d)\n"
247            "id           = %s\n"
248            "xres         = %d px\n"
249            "yres         = %d px\n"
250            "xres_virtual = %d px\n"
251            "yres_virtual = %d px\n"
252            "bpp          = %d\n"
253            "r            = %2u:%u\n"
254            "g            = %2u:%u\n"
255            "b            = %2u:%u\n",
256            fd,
257            finfo.id,
258            info.xres,
259            info.yres,
260            info.xres_virtual,
261            info.yres_virtual,
262            info.bits_per_pixel,
263            info.red.offset, info.red.length,
264            info.green.offset, info.green.length,
265            info.blue.offset, info.blue.length
266    );
267
268    LOGI(   "width        = %d mm (%f dpi)\n"
269            "height       = %d mm (%f dpi)\n"
270            "refresh rate = %.2f Hz\n",
271            info.width,  xdpi,
272            info.height, ydpi,
273            fps
274    );
275
276
277    if (ioctl(fd, FBIOGET_FSCREENINFO, &finfo) == -1)
278        return -errno;
279
280    if (finfo.smem_len <= 0)
281        return -errno;
282
283
284    module->flags = flags;
285    module->info = info;
286    module->finfo = finfo;
287    module->xdpi = xdpi;
288    module->ydpi = ydpi;
289    module->fps = fps;
290
291    /*
292     * map the framebuffer
293     */
294
295    int err;
296    size_t fbSize = roundUpToPageSize(finfo.line_length * info.yres_virtual);
297    module->framebuffer = new private_handle_t(dup(fd), fbSize,
298            private_handle_t::PRIV_FLAGS_USES_PMEM);
299
300    module->numBuffers = info.yres_virtual / info.yres;
301    module->bufferMask = 0;
302
303    void* vaddr = mmap(0, fbSize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
304    if (vaddr == MAP_FAILED) {
305        LOGE("Error mapping the framebuffer (%s)", strerror(errno));
306        return -errno;
307    }
308    module->framebuffer->base = intptr_t(vaddr);
309    memset(vaddr, 0, fbSize);
310    return 0;
311}
312
313static int mapFrameBuffer(struct private_module_t* module)
314{
315    pthread_mutex_lock(&module->lock);
316    int err = mapFrameBufferLocked(module);
317    pthread_mutex_unlock(&module->lock);
318    return err;
319}
320
321/*****************************************************************************/
322
323static int fb_close(struct hw_device_t *dev)
324{
325    fb_context_t* ctx = (fb_context_t*)dev;
326    if (ctx) {
327        free(ctx);
328    }
329    return 0;
330}
331
332int fb_device_open(hw_module_t const* module, const char* name,
333        hw_device_t** device)
334{
335    int status = -EINVAL;
336    if (!strcmp(name, GRALLOC_HARDWARE_FB0)) {
337
338        alloc_device_t* gralloc_device;
339        status = gralloc_open(module, &gralloc_device);
340        if (status < 0)
341            return status;
342
343        /* initialize our state here */
344        fb_context_t *dev = (fb_context_t*)malloc(sizeof(*dev));
345        memset(dev, 0, sizeof(*dev));
346
347        /* initialize the procs */
348        dev->device.common.tag = HARDWARE_DEVICE_TAG;
349        dev->device.common.version = 0;
350        dev->device.common.module = const_cast<hw_module_t*>(module);
351        dev->device.common.close = fb_close;
352        dev->device.setSwapInterval = fb_setSwapInterval;
353#if SUPPORTS_UPDATE_ON_DEMAND
354        dev->device.setUpdateRect   = fb_setUpdateRect;
355#endif
356        dev->device.post            = fb_post;
357
358        private_module_t* m = (private_module_t*)module;
359        status = mapFrameBuffer(m);
360        if (status >= 0) {
361            int stride = m->finfo.line_length / (m->info.bits_per_pixel >> 3);
362            const_cast<uint32_t&>(dev->device.flags) = 0;
363            const_cast<uint32_t&>(dev->device.width) = m->info.xres;
364            const_cast<uint32_t&>(dev->device.height) = m->info.yres;
365            const_cast<int&>(dev->device.stride) = stride;
366            const_cast<int&>(dev->device.format) = HAL_PIXEL_FORMAT_RGB_565;
367            const_cast<float&>(dev->device.xdpi) = m->xdpi;
368            const_cast<float&>(dev->device.ydpi) = m->ydpi;
369            const_cast<float&>(dev->device.fps) = m->fps;
370            const_cast<int&>(dev->device.minSwapInterval) = 1;
371            const_cast<int&>(dev->device.maxSwapInterval) = 1;
372
373            if (!strcmp(m->finfo.id, EMULATOR_DEV_FB_ID)) {
374                LOGD("I think we're running on the emulator, "
375                     "turning UPDATE_ON_DEMAND off");
376                dev->device.setUpdateRect = 0;
377            }
378
379            *device = &dev->device.common;
380        }
381    }
382    return status;
383}
384