sandbox: Add SDL library for LCD, keyboard, audio

SDL (Simple DirectMedia Layer - see www.libsdl.org) is a library which
provides simple graphics and sound features. It works under X11 and also
with a simple frame buffer interface. It is ideally suited to sandbox
U-Boot since it fits nicely with the low-level feature set required by
U-Boot. For example, U-Boot has its own font drawing routines, its own
keyboard processing and just needs raw sound output.

We can use SDL to provide emulation of these basic functions for sandbox.
This significantly expands the testing that is possible with sandbox.

Add a basic SDL library which we will use in future commits.

Tested-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 341 insertions, 0 deletions

diff --git a/arch/sandbox/cpu/sdl.c b/arch/sandbox/cpu/sdl.c
new file mode 100644
index 0000000..18dc7ed
--- /dev/null
+++ b/arch/sandbox/cpu/sdl.c
@@ -0,0 +1,341 @@
+/*
+ * Copyright (c) 2013 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <errno.h>
+#include <linux/input.h>
+#include <SDL/SDL.h>
+#include <sound.h>
+#include <asm/state.h>
+
+static struct sdl_info {
+	SDL_Surface *screen;
+	int width;
+	int height;
+	int depth;
+	int pitch;
+	uint frequency;
+	uint audio_pos;
+	uint audio_size;
+	uint8_t *audio_data;
+	bool audio_active;
+	bool inited;
+} sdl;
+
+static void sandbox_sdl_poll_events(void)
+{
+	/*
+	 * We don't want to include common.h in this file since it uses
+	 * system headers. So add a declation here.
+	 */
+	extern void reset_cpu(unsigned long addr);
+	SDL_Event event;
+
+	while (SDL_PollEvent(&event)) {
+		switch (event.type) {
+		case SDL_QUIT:
+			puts("LCD window closed - quitting\n");
+			reset_cpu(1);
+			break;
+		}
+	}
+}
+
+static int sandbox_sdl_ensure_init(void)
+{
+	if (!sdl.inited) {
+		if (SDL_Init(0) < 0) {
+			printf("Unable to initialize SDL: %s\n",
+			       SDL_GetError());
+			return -EIO;
+		}
+
+		atexit(SDL_Quit);
+
+		sdl.inited = true;
+	}
+	return 0;
+}
+
+int sandbox_sdl_init_display(int width, int height, int log2_bpp)
+{
+	struct sandbox_state *state = state_get_current();
+	int err;
+
+	if (!width || !state->show_lcd)
+		return 0;
+	err = sandbox_sdl_ensure_init();
+	if (err)
+		return err;
+	if (SDL_InitSubSystem(SDL_INIT_VIDEO) < 0) {
+		printf("Unable to initialize SDL LCD: %s\n", SDL_GetError());
+		return -EPERM;
+	}
+	SDL_WM_SetCaption("U-Boot", "U-Boot");
+
+	sdl.width = width;
+	sdl.height = height;
+	sdl.depth = 1 << log2_bpp;
+	sdl.pitch = sdl.width * sdl.depth / 8;
+	sdl.screen = SDL_SetVideoMode(width, height, 0, 0);
+	sandbox_sdl_poll_events();
+
+	return 0;
+}
+
+int sandbox_sdl_sync(void *lcd_base)
+{
+	SDL_Surface *frame;
+
+	frame = SDL_CreateRGBSurfaceFrom(lcd_base, sdl.width, sdl.height,
+			sdl.depth, sdl.pitch,
+			0x1f << 11, 0x3f << 5, 0x1f << 0, 0);
+	SDL_BlitSurface(frame, NULL, sdl.screen, NULL);
+	SDL_FreeSurface(frame);
+	SDL_UpdateRect(sdl.screen, 0, 0, 0, 0);
+	sandbox_sdl_poll_events();
+
+	return 0;
+}
+
+#define NONE (-1)
+#define NUM_SDL_CODES	(SDLK_UNDO + 1)
+
+static int16_t sdl_to_keycode[NUM_SDL_CODES] = {
+	/* 0 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, KEY_BACKSPACE, KEY_TAB,
+	NONE, NONE, NONE, KEY_ENTER, NONE,
+	NONE, NONE, NONE, NONE, KEY_POWER,	/* use PAUSE as POWER */
+
+	/* 20 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, KEY_ESC, NONE, NONE,
+	NONE, NONE, KEY_SPACE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 40 */
+	NONE, NONE, NONE, NONE, KEY_COMMA,
+	KEY_MINUS, KEY_DOT, KEY_SLASH, KEY_0, KEY_1,
+	KEY_2, KEY_3, KEY_4, KEY_5, KEY_6,
+	KEY_7, KEY_8, KEY_9, NONE, KEY_SEMICOLON,
+
+	/* 60 */
+	NONE, KEY_EQUAL, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 80 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, KEY_BACKSLASH, NONE, NONE,
+	NONE, KEY_GRAVE, KEY_A, KEY_B, KEY_C,
+
+	/* 100 */
+	KEY_D, KEY_E, KEY_F, KEY_G, KEY_H,
+	KEY_I, KEY_J, KEY_K, KEY_L, KEY_M,
+	KEY_N, KEY_O, KEY_P, KEY_Q, KEY_R,
+	KEY_S, KEY_T, KEY_U, KEY_V, KEY_W,
+
+	/* 120 */
+	KEY_X, KEY_Y, KEY_Z, NONE, NONE,
+	NONE, NONE, KEY_DELETE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 140 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 160 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 180 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 200 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 220 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 240 */
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+	NONE, KEY_KP0, KEY_KP1, KEY_KP2, KEY_KP3,
+
+	/* 260 */
+	KEY_KP4, KEY_KP5, KEY_KP6, KEY_KP7, KEY_KP8,
+	KEY_KP9, KEY_KPDOT, KEY_KPSLASH, KEY_KPASTERISK, KEY_KPMINUS,
+	KEY_KPPLUS, KEY_KPENTER, KEY_KPEQUAL, KEY_UP, KEY_DOWN,
+	KEY_RIGHT, KEY_LEFT, KEY_INSERT, KEY_HOME, KEY_END,
+
+	/* 280 */
+	KEY_PAGEUP, KEY_PAGEDOWN, KEY_F1, KEY_F2, KEY_F3,
+	KEY_F4, KEY_F5, KEY_F6, KEY_F7, KEY_F8,
+	KEY_F9, KEY_F10, KEY_F11, KEY_F12, NONE,
+	NONE, NONE, NONE, NONE, NONE,
+
+	/* 300 */
+	KEY_NUMLOCK, KEY_CAPSLOCK, KEY_SCROLLLOCK, KEY_RIGHTSHIFT,
+		KEY_LEFTSHIFT,
+	KEY_RIGHTCTRL, KEY_LEFTCTRL, KEY_RIGHTALT, KEY_LEFTALT, KEY_RIGHTMETA,
+	KEY_LEFTMETA, NONE, KEY_FN, NONE, KEY_COMPOSE,
+	NONE, KEY_PRINT, KEY_SYSRQ, KEY_PAUSE, NONE,
+
+	/* 320 */
+	NONE, NONE, NONE,
+};
+
+int sandbox_sdl_scan_keys(int key[], int max_keys)
+{
+	Uint8 *keystate;
+	int i, count;
+
+	sandbox_sdl_poll_events();
+	keystate = SDL_GetKeyState(NULL);
+	for (i = count = 0; i < NUM_SDL_CODES; i++) {
+		if (count >= max_keys)
+			break;
+		else if (keystate[i])
+			key[count++] = sdl_to_keycode[i];
+	}
+
+	return count;
+}
+
+int sandbox_sdl_key_pressed(int keycode)
+{
+	int key[8];	/* allow up to 8 keys to be pressed at once */
+	int count;
+	int i;
+
+	count = sandbox_sdl_scan_keys(key, sizeof(key) / sizeof(key[0]));
+	for (i = 0; i < count; i++) {
+		if (key[i] == keycode)
+			return 0;
+	}
+
+	return -ENOENT;
+}
+
+void sandbox_sdl_fill_audio(void *udata, Uint8 *stream, int len)
+{
+	int avail;
+
+	avail = sdl.audio_size - sdl.audio_pos;
+	if (avail < len)
+		len = avail;
+
+	SDL_MixAudio(stream, sdl.audio_data + sdl.audio_pos, len,
+		     SDL_MIX_MAXVOLUME);
+	sdl.audio_pos += len;
+
+	/* Loop if we are at the end */
+	if (sdl.audio_pos == sdl.audio_size)
+		sdl.audio_pos = 0;
+}
+
+int sandbox_sdl_sound_init(void)
+{
+	SDL_AudioSpec wanted;
+
+	if (sandbox_sdl_ensure_init())
+		return -1;
+
+	if (sdl.audio_active)
+		return 0;
+
+	/*
+	 * At present all sandbox sounds crash. This is probably due to
+	 * symbol name conflicts with U-Boot. We can remove the malloc()
+	 * probles with:
+	 *
+	 * #define USE_DL_PREFIX
+	 *
+	 * and get this:
+	 *
+	 * Assertion 'e->pollfd->fd == e->fd' failed at pulse/mainloop.c:676,
+	 *		function dispatch_pollfds(). Aborting.
+	 *
+	 * The right solution is probably to make U-Boot's names private or
+	 * link os.c and sdl.c against their libraries before liking with
+	 * U-Boot. TBD. For now sound is disabled.
+	 */
+	printf("(Warning: sandbox sound disabled)\n");
+	return 0;
+
+	/* Set the audio format */
+	wanted.freq = 22050;
+	wanted.format = AUDIO_S16;
+	wanted.channels = 1;    /* 1 = mono, 2 = stereo */
+	wanted.samples = 1024;  /* Good low-latency value for callback */
+	wanted.callback = sandbox_sdl_fill_audio;
+	wanted.userdata = NULL;
+
+	sdl.audio_size = sizeof(uint16_t) * wanted.freq;
+	sdl.audio_data = malloc(sdl.audio_size);
+	if (!sdl.audio_data) {
+		printf("%s: Out of memory\n", __func__);
+		return -1;
+	}
+	sdl.audio_pos = 0;
+
+	if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) {
+		printf("Unable to initialize SDL audio: %s\n", SDL_GetError());
+		goto err;
+	}
+
+	/* Open the audio device, forcing the desired format */
+	if (SDL_OpenAudio(&wanted, NULL) < 0) {
+		printf("Couldn't open audio: %s\n", SDL_GetError());
+		goto err;
+	}
+	sdl.audio_active = true;
+
+	return 0;
+
+err:
+	free(sdl.audio_data);
+	return -1;
+}
+
+int sandbox_sdl_sound_start(uint frequency)
+{
+	if (!sdl.audio_active)
+		return -1;
+	sdl.frequency = frequency;
+	sound_create_square_wave((unsigned short *)sdl.audio_data,
+				 sdl.audio_size, frequency);
+	sdl.audio_pos = 0;
+	SDL_PauseAudio(0);
+
+	return 0;
+}
+
+int sandbox_sdl_sound_stop(void)
+{
+	if (!sdl.audio_active)
+		return -1;
+	SDL_PauseAudio(1);
+
+	return 0;
+}