哇酷®开发者社区(WhyCan® Forum)

/**

• fdt_setup_simplefb_node - Fill and enable a simplefb node
  *

• @fdt: ptr to device tree

• @node: offset of the simplefb node

• @base_address: framebuffer base address

• @width: width in pixels

• @height: height in pixels

• @stride: bytes per line

• @format: pixel format string
  *

• Convenience function to fill and enable a simplefb node.
  */
  int fdt_setup_simplefb_node(void *fdt, int node, u64 base_address, u32 width,
  u32 height, u32 stride, const char *format)
  {
  char name[32];
  fdt32_t cells[4];
  int i, addrc, sizec, ret;

of_bus_default_count_cells(fdt, fdt_parent_offset(fdt, node),
&addrc, &sizec);
i = 0;
if (addrc == 2)
cells[i++] = cpu_to_fdt32(base_address >> 32);
cells[i++] = cpu_to_fdt32(base_address);
if (sizec == 2)
cells[i++] = 0;
cells[i++] = cpu_to_fdt32(height * stride);

ret = fdt_setprop(fdt, node, "reg", cells, sizeof(cells[0]) * i);
if (ret < 0)
return ret;

snprintf(name, sizeof(name), "framebuffer@%" PRIx64, base_address);
ret = fdt_set_name(fdt, node, name);
if (ret < 0)
return ret;

ret = fdt_setprop_u32(fdt, node, "width", width);
if (ret < 0)
return ret;

ret = fdt_setprop_u32(fdt, node, "height", height);
if (ret < 0)
return ret;

ret = fdt_setprop_u32(fdt, node, "stride", stride);
if (ret < 0)
return ret;

ret = fdt_setprop_string(fdt, node, "format", format);
if (ret < 0)
return ret;

ret = fdt_setprop_string(fdt, node, "status", "okay");
if (ret < 0)
return ret;

return 0;
}

晕哥 wrote:

这个问题我以前也纳闷过，
后来发现 u-boot的 common/fdt_support.c 里面有 fdt_setup_simplefb_node()这个函数，
他居然会自己创建设备树, 然后传递给Linux用，赶脚好神奇！

smartcar wrote:

hanzixi_angel wrote:

晕哥 wrote:

这个问题我以前也纳闷过，
后来发现 u-boot的 common/fdt_support.c 里面有 fdt_setup_simplefb_node()这个函数，
他居然会自己创建设备树, 然后传递给Linux用，赶脚好神奇！

晕哥 如何使用de功能 在Linux设备树中更改lcd屏幕的参数 现在都是更改linux/drivers/gpu/drm/panel/panel-simple.c源码 然后编译镜像之后烧写 以后会有多种屏幕 这样不太方便 最好只修改设备树 在设备树配置参数 只更换设备树即可 这样最好

你的de功能正常了吗?