From 106b4a2a78b2a2f14885604891957b84bba502db Mon Sep 17 00:00:00 2001 From: Adrian Betschart Date: Fri, 11 Sep 2026 17:13:14 +0200 Subject: drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validation amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart Reviewed-by: Fangzhi Zuo Tested-by: Adolfo Rodrigues Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7) --- arch/alpha/boot/misc.c | 172 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 172 insertions(+) create mode 100644 arch/alpha/boot/misc.c (limited to 'arch/alpha/boot/misc.c') diff --git a/arch/alpha/boot/misc.c b/arch/alpha/boot/misc.c new file mode 100644 index 000000000..1ab91852d --- /dev/null +++ b/arch/alpha/boot/misc.c @@ -0,0 +1,172 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * misc.c + * + * This is a collection of several routines from gzip-1.0.3 + * adapted for Linux. + * + * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994 + * + * Modified for ARM Linux by Russell King + * + * Nicolas Pitre 1999/04/14 : + * For this code to run directly from Flash, all constant variables must + * be marked with 'const' and all other variables initialized at run-time + * only. This way all non constant variables will end up in the bss segment, + * which should point to addresses in RAM and cleared to 0 on start. + * This allows for a much quicker boot time. + * + * Modified for Alpha, from the ARM version, by Jay Estabrook 2003. + */ + +#include +#include + +#include + +#define memzero(s,n) memset ((s),0,(n)) +#define puts srm_printk +extern long srm_printk(const char *, ...) + __attribute__ ((format (printf, 1, 2))); + +/* + * gzip declarations + */ +#define OF(args) args +#define STATIC static + +typedef unsigned char uch; +typedef unsigned short ush; +typedef unsigned long ulg; + +#define WSIZE 0x8000 /* Window size must be at least 32k, */ + /* and a power of two */ + +static uch *inbuf; /* input buffer */ +static uch *window; /* Sliding window buffer */ + +static unsigned insize; /* valid bytes in inbuf */ +static unsigned inptr; /* index of next byte to be processed in inbuf */ +static unsigned outcnt; /* bytes in output buffer */ + +/* gzip flag byte */ +#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ +#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ +#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ +#define ORIG_NAME 0x08 /* bit 3 set: original file name present */ +#define COMMENT 0x10 /* bit 4 set: file comment present */ +#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ +#define RESERVED 0xC0 /* bit 6,7: reserved */ + +#define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf()) + +/* Diagnostic functions */ +#ifdef DEBUG +# define Assert(cond,msg) {if(!(cond)) error(msg);} +# define Trace(x) fprintf x +# define Tracev(x) {if (verbose) fprintf x ;} +# define Tracevv(x) {if (verbose>1) fprintf x ;} +# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} +# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} +#else +# define Assert(cond,msg) +# define Trace(x) +# define Tracev(x) +# define Tracevv(x) +# define Tracec(c,x) +# define Tracecv(c,x) +#endif + +static int fill_inbuf(void); +static void flush_window(void); +static void error(char *m); + +static char *input_data; +static int input_data_size; + +static uch *output_data; +static ulg output_ptr; +static ulg bytes_out; + +static void error(char *m); + +extern int end; +static ulg free_mem_ptr; +static ulg free_mem_end_ptr; + +#define HEAP_SIZE 0x3000 + +#include "../../../lib/inflate.c" + +/* =========================================================================== + * Fill the input buffer. This is called only when the buffer is empty + * and at least one byte is really needed. + */ +int fill_inbuf(void) +{ + if (insize != 0) + error("ran out of input data"); + + inbuf = input_data; + insize = input_data_size; + + inptr = 1; + return inbuf[0]; +} + +/* =========================================================================== + * Write the output window window[0..outcnt-1] and update crc and bytes_out. + * (Used for the decompressed data only.) + */ +void flush_window(void) +{ + ulg c = crc; + unsigned n; + uch *in, *out, ch; + + in = window; + out = &output_data[output_ptr]; + for (n = 0; n < outcnt; n++) { + ch = *out++ = *in++; + c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8); + } + crc = c; + bytes_out += (ulg)outcnt; + output_ptr += (ulg)outcnt; + outcnt = 0; +/* puts("."); */ +} + +static void error(char *x) +{ + puts("\n\n"); + puts(x); + puts("\n\n -- System halted"); + + while(1); /* Halt */ +} + +unsigned int +decompress_kernel(void *output_start, + void *input_start, + size_t ksize, + size_t kzsize) +{ + output_data = (uch *)output_start; + input_data = (uch *)input_start; + input_data_size = kzsize; /* use compressed size */ + + /* FIXME FIXME FIXME */ + free_mem_ptr = (ulg)output_start + ksize; + free_mem_end_ptr = (ulg)output_start + ksize + 0x200000; + /* FIXME FIXME FIXME */ + + /* put in temp area to reduce initial footprint */ + window = malloc(WSIZE); + + makecrc(); +/* puts("Uncompressing Linux..."); */ + gunzip(); +/* puts(" done, booting the kernel.\n"); */ + return output_ptr; +} -- cgit v1.3.1