[U-Boot] [PATCH v1 08/12] efi_loader: console support for color attributes

Heinrich Schuchardt
2017-10-04T18:53:00Z

On 09/10/2017 03:22 PM, Rob Clark wrote:
> Shell.efi uses this, and supporting color attributes makes things look
> nicer. Map the EFI fg/bg color attributes to ANSI escape sequences.
> Not all colors have a perfect match, but spec just says "Devices
> supporting a different number of text colors are required to emulate the
> above colors to the best of the device’s capabilities".
>
> Signed-off-by: Rob Clark <robdclark@gmail.com>
> ---
> include/efi_api.h | 29 +++++++++++++++++++++++++++++
> lib/efi_loader/efi_console.c | 30 ++++++++++++++++++++++++++++++
> 2 files changed, 59 insertions(+)
>
> diff --git a/include/efi_api.h b/include/efi_api.h
> index 87c8ffe68e..3cc1dbac2e 100644
> --- a/include/efi_api.h
> +++ b/include/efi_api.h
> @@ -426,6 +426,35 @@ struct simple_text_output_mode {
> EFI_GUID(0x387477c2, 0x69c7, 0x11d2, \
> 0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
>
> +#define EFI_BLACK 0x00
> +#define EFI_BLUE 0x01
> +#define EFI_GREEN 0x02
> +#define EFI_CYAN 0x03
> +#define EFI_RED 0x04
> +#define EFI_MAGENTA 0x05
> +#define EFI_BROWN 0x06
> +#define EFI_LIGHTGRAY 0x07
> +#define EFI_BRIGHT 0x08
> +#define EFI_DARKGRAY 0x08
> +#define EFI_LIGHTBLUE 0x09
> +#define EFI_LIGHTGREEN 0x0a
> +#define EFI_LIGHTCYAN 0x0b
> +#define EFI_LIGHTRED 0x0c
> +#define EFI_LIGHTMAGENTA 0x0d
> +#define EFI_YELLOW 0x0e
> +#define EFI_WHITE 0x0f
> +#define EFI_BACKGROUND_BLACK 0x00
> +#define EFI_BACKGROUND_BLUE 0x10
> +#define EFI_BACKGROUND_GREEN 0x20
> +#define EFI_BACKGROUND_CYAN 0x30
> +#define EFI_BACKGROUND_RED 0x40
> +#define EFI_BACKGROUND_MAGENTA 0x50
> +#define EFI_BACKGROUND_BROWN 0x60
> +#define EFI_BACKGROUND_LIGHTGRAY 0x70

Will we ever use these constants?

Where are the comments explaining the defines below?

> +
> +#define EFI_ATTR_FG(attr) ((attr) & 0x0f)

This saves 8 entries in the table below.
+#define EFI_ATTR_FG(attr) ((attr) & 0x07)

> +#define EFI_ATTR_BG(attr) (((attr) >> 4) & 0x7)

Add
#define EFI_ATTR_BOLD(attr) (((attr) >> 3) & 0x01)

> +
> struct efi_simple_text_output_protocol {
> void *reset;
> efi_status_t (EFIAPI *output_string)(
> diff --git a/lib/efi_loader/efi_console.c b/lib/efi_loader/efi_console.c
> index 2e13fdc096..fcd65ca488 100644
> --- a/lib/efi_loader/efi_console.c
> +++ b/lib/efi_loader/efi_console.c
> @@ -316,12 +316,42 @@ static efi_status_t EFIAPI efi_cout_set_mode(
> return EFI_EXIT(EFI_SUCCESS);
> }
>
> +static const struct {
> + unsigned fg;
> + unsigned bg;
> +} color[] = {
> + { 30, 40 }, /* 0: black */
> + { 34, 44 }, /* 1: blue */
> + { 32, 42 }, /* 2: green */
> + { 36, 46 }, /* 3: cyan */
> + { 31, 41 }, /* 4: red */
> + { 35, 45 }, /* 5: magenta */
> + { 30, 40 }, /* 6: brown, map to black */

This should be { 33, 43 }

> + { 37, 47 }, /* 7: light grey, map to white */

The entries below are redundant.

> + { 37, 47 }, /* 8: bright, map to white */
> + { 34, 44 }, /* 9: light blue, map to blue */
> + { 32, 42 }, /* A: light green, map to green */
> + { 36, 46 }, /* B: light cyan, map to cyan */
> + { 31, 41 }, /* C: light red, map to red */
> + { 35, 45 }, /* D: light magenta, map to magenta */
> + { 33, 43 }, /* E: yellow */
> + { 37, 47 }, /* F: white */
> +};
> +

No function without a comment explaining the parameters.

> static efi_status_t EFIAPI efi_cout_set_attribute(
> struct efi_simple_text_output_protocol *this,
> unsigned long attribute)
> {
> + unsigned fg = EFI_ATTR_FG(attribute);
> + unsigned bg = EFI_ATTR_BG(attribute);

Use unsigned int.

> +
> EFI_ENTRY("%p, %lx", this, attribute);
>
> + if (attribute)

Attribute 0 should be black on black. No need for any if here.

> + printf(ESC"[%u;%um", color[fg].fg, color[bg].bg);

Use bold for light colors.

unsigned int bold;
if (EFI_ATTRIB_BOLD(attr))
bold = 1;
else
bold = 22;

printf(ESC"[%u;%u;%um", bold, color[fg].fg, color[bg].bg)

Best regards

Heinrich

> + else
> + printf(ESC"[37;40m");

> +
> /* Just ignore attributes (colors) for now */
> return EFI_EXIT(EFI_UNSUPPORTED);
> }
>