[PATCH 4/4] arm/raspberrypi: add VideoCore framebuffer without initialization

Pavel Pisa ppisa4lists at pikron.com
Thu Apr 28 11:29:39 UTC 2016


From: YANG Qiao <yangqiao0505 at me.com>
Date: Thu, 13 Aug 2015 00:06:10 +0200

---
 c/src/lib/libbsp/arm/raspberrypi/Makefile.am  |   1 +
 c/src/lib/libbsp/arm/raspberrypi/console/fb.c | 331 ++++++++++++++++++++++++++
 2 files changed, 332 insertions(+)
 create mode 100644 c/src/lib/libbsp/arm/raspberrypi/console/fb.c

diff --git a/c/src/lib/libbsp/arm/raspberrypi/Makefile.am b/c/src/lib/libbsp/arm/raspberrypi/Makefile.am
index 258f8a0..77935dc 100644
--- a/c/src/lib/libbsp/arm/raspberrypi/Makefile.am
+++ b/c/src/lib/libbsp/arm/raspberrypi/Makefile.am
@@ -114,6 +114,7 @@ libbsp_a_SOURCES += ../../shared/console_select.c
 libbsp_a_SOURCES += ../../shared/console_write.c
 libbsp_a_SOURCES += console/console-config.c
 libbsp_a_SOURCES += console/usart.c
+libbsp_a_SOURCES += console/fb.c
 
 # Mailbox
 libbsp_a_SOURCES += misc/mailbox.c
diff --git a/c/src/lib/libbsp/arm/raspberrypi/console/fb.c b/c/src/lib/libbsp/arm/raspberrypi/console/fb.c
new file mode 100644
index 0000000..a83d560
--- /dev/null
+++ b/c/src/lib/libbsp/arm/raspberrypi/console/fb.c
@@ -0,0 +1,331 @@
+/**
+ * @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 <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 <rtems.h>
+#include <rtems/libio.h>
+#include <rtems/fb.h>
+#include <rtems/framebuffer.h>
+#include <rtems/score/atomic.h>
+
+#define SCREEN_WIDTH 1024
+#define SCREEN_HEIGHT 768
+#define BPP 32
+#define BUFFER_SIZE (SCREEN_WIDTH*SCREEN_HEIGHT*BPP/8)
+
+/* 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
+};
+
+int raspberrypi_get_fix_screen_info( struct fb_fix_screeninfo *info )
+{
+  *info = fb_fix_info;
+  return 0;
+}
+
+int raspberrypi_get_var_screen_info( struct fb_var_screeninfo *info )
+{
+  *info = fb_var_info;
+  return 0;
+}
+
+static int
+find_mode_from_cmdline(void)
+{
+  const char* opt;
+  char* endptr;
+  uint32_t width;
+  uint32_t height;
+  uint32_t bpp;
+  opt = rpi_cmdline_arg("--video=");
+  if (opt)
+  {
+      opt += sizeof("--video=")-1;
+      width = strtol(opt, &endptr, 10);
+      if (*endptr != 'x')
+      {
+          return -2;
+      }
+      opt = endptr+1;
+      height = strtol(opt, &endptr, 10);
+      switch (*endptr)
+      {
+          case '-':
+              opt = endptr+1;
+              if (strlen(opt) <= 2)
+                  bpp = strtol(opt, &endptr, 10);
+              else
+              {
+                  bpp = strtol(opt, &endptr, 10);
+                  if (*endptr != ' ')
+                  {
+                      return -4;
+                  }
+              }
+          case ' ':
+          case 0:
+              break;
+          default:
+              return -3;
+      }
+  }
+  else
+    return -1;
+
+  fb_var_info.xres    = width;
+  fb_var_info.yres    = height;
+
+  return 0;
+}
+
+static int
+find_mode_from_vc(void)
+{
+  bcm2835_get_display_size_entries entries;
+  bcm2835_mailbox_get_display_size(&entries);
+  unsigned int width = entries.width;
+  unsigned int 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;
+  }
+
+  return 0;
+}
+
+static bool
+hdmi_is_present(void)
+{
+  bcm2835_get_display_size_entries entries;
+  bcm2835_mailbox_get_display_size(&entries);
+  if(entries.width == 0x290 && entries.height ==0x1A0 )
+  {
+    return false;
+  }
+  else
+  {
+    return true;
+  }
+}
+
+int
+fb_init(void)
+{
+  if (fb_fix_info.smem_start != NULL)
+  {
+    return -2;
+  }
+
+  if (hdmi_is_present() == false)
+  {
+    return -3;
+  }
+
+  if (find_mode_from_cmdline())
+  {
+    if(find_mode_from_vc())
+      return -1;
+  }
+
+  bcm2835_init_frame_buffer_entries  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;
+  bcm2835_mailbox_init_frame_buffer(&init_frame_buffer_entries);
+
+  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 = init_frame_buffer_entries.base;
+  fb_fix_info.smem_len = init_frame_buffer_entries.size;
+  fb_fix_info.line_length = get_pitch_entries.pitch;
+
+  return 0;
+}
+
+
+/*
+ * 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( "FB_CIRRUS could not lock driver_mutex\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() */
+  _Atomic_Flag_clear(&driver_mutex, ATOMIC_ORDER_RELEASE);
+  memset ((void *)fb_fix_info.smem_start, 0, fb_fix_info.smem_len);
+  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:
+    args->ioctl_return = 0;
+    break;
+  case FBIOPUTCMAP:
+    args->ioctl_return = 0;
+    break;
+
+  default:
+    args->ioctl_return = 0;
+    break;
+
+  }
+  return RTEMS_SUCCESSFUL;
+}
-- 
1.9.1




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