/**
* @file
*
* @ingroup raspberrypi
*
* @brief framebuffer support.
*/
/*
* Copyright (c) 2015 Yang Qiao
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
*
* http://www.rtems.org/license/LICENSE
*
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <sys/types.h>
#include <bsp.h>
#include <bsp/raspberrypi.h>
#include <bsp/mailbox.h>
#include <bsp/vc.h>
#include <bsp/rpi-fb.h>
#include <libcpu/arm-cp15.h>
#include <rtems.h>
#include <rtems/libio.h>
#include <rtems/fb.h>
#include <rtems/framebuffer.h>
#include <rtems/score/atomic.h>
#include <rtems/bspIo.h>
#define SCREEN_WIDTH 1024
#define SCREEN_HEIGHT 768
#define BPP 32
/* flag to limit driver to protect against multiple opens */
static Atomic_Flag driver_mutex;
/*
* screen information for the driver (fb0).
*/
static struct fb_var_screeninfo fb_var_info = {
.xres = SCREEN_WIDTH,
.yres = SCREEN_HEIGHT,
.bits_per_pixel = BPP
};
static struct fb_fix_screeninfo fb_fix_info = {
.smem_start = (void *) NULL,
.smem_len = 0,
.type = FB_TYPE_PACKED_PIXELS,
.visual = FB_VISUAL_TRUECOLOR,
.line_length = 0
};
typedef enum {
NO_SUITABLE_MODE = -1,
BAD_FORMAT = -2,
AUTO_SELECT = -3,
DONT_INIT = -4,
NO_MODE_REQ = -5,
} mode_err_ret_val;
int rpi_get_fix_screen_info( struct fb_fix_screeninfo *info )
{
*info = fb_fix_info;
return 0;
}
int rpi_get_var_screen_info( struct fb_var_screeninfo *info )
{
*info = fb_var_info;
return 0;
}
/**
* @brief Find mode given in string format.
*
* expected format
* <resX>x<resY>[-<bpp>]
* numbers <resX>, <resY> and <bpp> are decadic
*
* @param[out] fb_var_ptr pointer to variable mode part filled by function
* @param[in] video_string string to be parsed
* @retval video mode number to be set
* @retval -1 no suitable mode found
* @retval -2 bad format of the video_string
* @retval -3 automatic mode selection requested
* @retval -4 request to not initialize graphics
* @retval -5 no mode requested/empty video string
*/
static int parse_mode_from_string(
struct fb_var_screeninfo *fb_var_ptr,
const char *video_string
)
{
const char *opt;
char *endptr;
uint32_t width;
uint32_t height;
uint32_t bpp = 0;
opt = video_string;
if ( opt == NULL )
return NO_MODE_REQ;
if ( strncmp( opt, "auto", 4 ) == 0 )
return AUTO_SELECT;
if ( strncmp( opt, "none", 4 ) == 0 ||
strncmp( opt, "off", 3 ) == 0 )
return DONT_INIT;
width = strtol( opt, &endptr, 10 );
if ( *endptr != 'x' ) {
return BAD_FORMAT;
}
opt = endptr + 1;
height = strtol( opt, &endptr, 10 );
switch ( *endptr ) {
case '-':
opt = endptr + 1;
endptr = NULL;
bpp = strtol( opt, &endptr, 10 );
if ( ( endptr == opt ) || ( endptr == NULL ) )
return BAD_FORMAT;
if ( *endptr && ( *endptr != ' ' ) )
return BAD_FORMAT;
break;
case ' ':
case 0:
break;
default:
return BAD_FORMAT;
}
fb_var_ptr->xres = width;
fb_var_ptr->yres = height;
if ( bpp != 0 )
fb_var_ptr->bits_per_pixel = bpp;
return 0;
}
static int find_mode_from_vc( void )
{
int res;
unsigned int width;
unsigned int height;
bcm2835_get_display_size_entries entries;
res = bcm2835_mailbox_get_display_size( &entries );
width = entries.width;
height = entries.height;
if ( width == 0 || height == 0 ) {
fb_var_info.xres = SCREEN_WIDTH;
fb_var_info.yres = SCREEN_HEIGHT;
} else {
fb_var_info.xres = width;
fb_var_info.yres = height;
}
printk("find_mode_from_vc %u x %u, res %d\n", width, height, res);
return res;
}
bool rpi_fb_hdmi_is_present( void )
{
bcm2835_get_display_size_entries entries;
memset( &entries, 0, sizeof( entries ) );
bcm2835_mailbox_get_display_size( &entries );
/* Impossible display dimension */
if ( ( entries.width < 10 ) || ( entries.height < 10 ) )
return false;
/* Know default values reported when monitor is not present */
if ( ( entries.width == 0x290 ) && ( entries.height == 0x1A0 ) )
return false;
return true;
}
int rpi_fb_init( void )
{
int res;
int mode_from_cmdline;
bcm2835_init_frame_buffer_entries init_frame_buffer_entries;
if ( fb_fix_info.smem_start != NULL ) {
return RPI_FB_INIT_ALREADY_INITIALIZED;
}
if ( rpi_fb_hdmi_is_present() == false ) {
return RPI_FB_INIT_NO_DISPLAY;
}
mode_from_cmdline = parse_mode_from_string( &fb_var_info,
rpi_cmdline_get_arg( "--video=" ) );
switch ( mode_from_cmdline ) {
case BAD_FORMAT:
return RPI_FB_INIT_CMDLINE_BAD_FORMAT;
case AUTO_SELECT:
break;
case DONT_INIT:
return RPI_FB_INIT_CMDLINE_DONT_INIT;
case NO_MODE_REQ:
return RPI_FB_INIT_CMDLINE_NO_MODE_REQ;
}
if ( mode_from_cmdline ) {
if ( find_mode_from_vc() )
return RPI_FB_INIT_MODE_PROBE_ERROR;
}
memset( &init_frame_buffer_entries, 0, sizeof( init_frame_buffer_entries ) );
init_frame_buffer_entries.xres = fb_var_info.xres;
init_frame_buffer_entries.yres = fb_var_info.yres;
init_frame_buffer_entries.xvirt = fb_var_info.xres;
init_frame_buffer_entries.yvirt = fb_var_info.yres;
init_frame_buffer_entries.depth = fb_var_info.bits_per_pixel;
init_frame_buffer_entries.pixel_order = bcm2835_mailbox_pixel_order_rgb;
init_frame_buffer_entries.alpha_mode = bcm2835_mailbox_alpha_mode_0_opaque;
init_frame_buffer_entries.voffset_x = 0;
init_frame_buffer_entries.voffset_y = 0;
init_frame_buffer_entries.overscan_left = 0;
init_frame_buffer_entries.overscan_right = 0;
init_frame_buffer_entries.overscan_top = 0;
init_frame_buffer_entries.overscan_bottom = 0;
printk("bcm2835_mailbox_init_frame_buffer ...\n");
res = bcm2835_mailbox_init_frame_buffer( &init_frame_buffer_entries );
printk("bcm2835_mailbox_init_frame_buffer returned %d\n", res);
if (res != 0) {
printk("bcm2835_mailbox_init_frame_buffer retry ...\n");
res = bcm2835_mailbox_init_frame_buffer( &init_frame_buffer_entries );
printk("bcm2835_mailbox_init_frame_buffer returned %d\n", res);
if (res != 0)
return RPI_FB_INIT_SETUP_FAILED;
}
bcm2835_get_pitch_entries get_pitch_entries;
bcm2835_mailbox_get_pitch( &get_pitch_entries );
fb_var_info.xres = init_frame_buffer_entries.xres;
fb_var_info.yres = init_frame_buffer_entries.yres;
fb_var_info.bits_per_pixel = init_frame_buffer_entries.depth;
fb_fix_info.smem_start = (void *) init_frame_buffer_entries.base;
fb_fix_info.smem_len = init_frame_buffer_entries.size;
fb_fix_info.line_length = get_pitch_entries.pitch;
if ( fb_fix_info.smem_start == NULL )
return RPI_FB_INIT_START_ADDR_UNKNOWN;
printk("fb_fix_info.smem_start %p\n", fb_fix_info.smem_start);
arm_cp15_set_translation_table_entries( (void *) fb_fix_info.smem_start,
(void *) fb_fix_info.smem_start +
fb_fix_info.smem_len,
ARMV7_MMU_DATA_READ_WRITE_CACHED );
return RPI_FB_INIT_OK;
}
/*
* fbds device driver initialize entry point.
*/
rtems_device_driver frame_buffer_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_status_code status;
/* register the devices */
status = rtems_io_register_name( FRAMEBUFFER_DEVICE_0_NAME, major, 0 );
if ( status != RTEMS_SUCCESSFUL ) {
printk( "[!] error registering framebuffer\n" );
rtems_fatal_error_occurred( status );
}
_Atomic_Flag_clear( &driver_mutex, ATOMIC_ORDER_RELEASE );
return RTEMS_SUCCESSFUL;
}
/*
* fbds device driver open operation.
*/
rtems_device_driver frame_buffer_open(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
if ( _Atomic_Flag_test_and_set( &driver_mutex,
ATOMIC_ORDER_ACQUIRE ) != 0 ) {
printk( "RaspberryPi framebuffer could not lock driver_mutex\n" );
return RTEMS_UNSATISFIED;
}
if ( fb_fix_info.smem_start == NULL ) {
int res;
res = rpi_fb_init();
if ( (res < RPI_FB_INIT_OK) || (fb_fix_info.smem_start == NULL) ) {
_Atomic_Flag_clear( &driver_mutex, ATOMIC_ORDER_RELEASE );
printk( "RaspberryPi framebuffer initialization failed\n" );
return RTEMS_UNSATISFIED;
}
}
memset( (void *) fb_fix_info.smem_start, 0, fb_fix_info.smem_len );
return RTEMS_SUCCESSFUL;
}
/*
* fbds device driver close operation.
*/
rtems_device_driver frame_buffer_close(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
/* restore previous state. for VGA this means return to text mode.
* leave out if graphics hardware has been initialized in
* frame_buffer_initialize() */
memset( (void *) fb_fix_info.smem_start, 0, fb_fix_info.smem_len );
_Atomic_Flag_clear( &driver_mutex, ATOMIC_ORDER_RELEASE );
return RTEMS_SUCCESSFUL;
}
/*
* fbds device driver read operation.
*/
rtems_device_driver frame_buffer_read(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_libio_rw_args_t *rw_args = (rtems_libio_rw_args_t *) arg;
rw_args->bytes_moved =
( ( rw_args->offset + rw_args->count ) > fb_fix_info.smem_len ) ?
( fb_fix_info.smem_len - rw_args->offset ) : rw_args->count;
memcpy( rw_args->buffer,
(const void *) ( fb_fix_info.smem_start + rw_args->offset ),
rw_args->bytes_moved );
return RTEMS_SUCCESSFUL;
}
/*
* fbds device driver write operation.
*/
rtems_device_driver frame_buffer_write(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_libio_rw_args_t *rw_args = (rtems_libio_rw_args_t *) arg;
rw_args->bytes_moved =
( ( rw_args->offset + rw_args->count ) > fb_fix_info.smem_len ) ?
( fb_fix_info.smem_len - rw_args->offset ) : rw_args->count;
memcpy( (void *) ( fb_fix_info.smem_start + rw_args->offset ),
rw_args->buffer,
rw_args->bytes_moved );
return RTEMS_SUCCESSFUL;
}
/*
* ioctl entry point.
*/
rtems_device_driver frame_buffer_control(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_libio_ioctl_args_t *args = arg;
/* XXX check minor */
switch ( args->command ) {
case FBIOGET_VSCREENINFO:
memcpy( args->buffer, &fb_var_info, sizeof( fb_var_info ) );
args->ioctl_return = 0;
break;
case FBIOGET_FSCREENINFO:
memcpy( args->buffer, &fb_fix_info, sizeof( fb_fix_info ) );
args->ioctl_return = 0;
break;
case FBIOGETCMAP:
/* no palette - truecolor mode */
args->ioctl_return = -1;
return RTEMS_UNSATISFIED;
case FBIOPUTCMAP:
/* no palette - truecolor mode */
args->ioctl_return = -1;
return RTEMS_UNSATISFIED;
default:
args->ioctl_return = -1;
return RTEMS_UNSATISFIED;
}
return RTEMS_SUCCESSFUL;
}
