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/lib/memset.S | 133 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 133 insertions(+) create mode 100644 arch/alpha/lib/memset.S (limited to 'arch/alpha/lib/memset.S') diff --git a/arch/alpha/lib/memset.S b/arch/alpha/lib/memset.S new file mode 100644 index 000000000..9075d6918 --- /dev/null +++ b/arch/alpha/lib/memset.S @@ -0,0 +1,133 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * linux/arch/alpha/lib/memset.S + * + * This is an efficient (and small) implementation of the C library "memset()" + * function for the alpha. + * + * (C) Copyright 1996 Linus Torvalds + * + * This routine is "moral-ware": you are free to use it any way you wish, and + * the only obligation I put on you is a moral one: if you make any improvements + * to the routine, please send me your improvements for me to use similarly. + * + * The scheduling comments are according to the EV5 documentation (and done by + * hand, so they might well be incorrect, please do tell me about it..) + */ +#include + .set noat + .set noreorder +.text + .globl memset + .globl __memset + .globl ___memset + .globl __memset16 + .globl __constant_c_memset + + .ent ___memset +.align 5 +___memset: + .frame $30,0,$26,0 + .prologue 0 + + and $17,255,$1 /* E1 */ + insbl $17,1,$17 /* .. E0 */ + bis $17,$1,$17 /* E0 (p-c latency, next cycle) */ + sll $17,16,$1 /* E1 (p-c latency, next cycle) */ + + bis $17,$1,$17 /* E0 (p-c latency, next cycle) */ + sll $17,32,$1 /* E1 (p-c latency, next cycle) */ + bis $17,$1,$17 /* E0 (p-c latency, next cycle) */ + ldq_u $31,0($30) /* .. E1 */ + +.align 5 +__constant_c_memset: + addq $18,$16,$6 /* E0 */ + bis $16,$16,$0 /* .. E1 */ + xor $16,$6,$1 /* E0 */ + ble $18,end /* .. E1 */ + + bic $1,7,$1 /* E0 */ + beq $1,within_one_quad /* .. E1 (note EV5 zero-latency forwarding) */ + and $16,7,$3 /* E0 */ + beq $3,aligned /* .. E1 (note EV5 zero-latency forwarding) */ + + ldq_u $4,0($16) /* E0 */ + bis $16,$16,$5 /* .. E1 */ + insql $17,$16,$2 /* E0 */ + subq $3,8,$3 /* .. E1 */ + + addq $18,$3,$18 /* E0 $18 is new count ($3 is negative) */ + mskql $4,$16,$4 /* .. E1 (and possible load stall) */ + subq $16,$3,$16 /* E0 $16 is new aligned destination */ + bis $2,$4,$1 /* .. E1 */ + + bis $31,$31,$31 /* E0 */ + ldq_u $31,0($30) /* .. E1 */ + stq_u $1,0($5) /* E0 */ + bis $31,$31,$31 /* .. E1 */ + +.align 4 +aligned: + sra $18,3,$3 /* E0 */ + and $18,7,$18 /* .. E1 */ + bis $16,$16,$5 /* E0 */ + beq $3,no_quad /* .. E1 */ + +.align 3 +loop: + stq $17,0($5) /* E0 */ + subq $3,1,$3 /* .. E1 */ + addq $5,8,$5 /* E0 */ + bne $3,loop /* .. E1 */ + +no_quad: + bis $31,$31,$31 /* E0 */ + beq $18,end /* .. E1 */ + ldq $7,0($5) /* E0 */ + mskqh $7,$6,$2 /* .. E1 (and load stall) */ + + insqh $17,$6,$4 /* E0 */ + bis $2,$4,$1 /* .. E1 */ + stq $1,0($5) /* E0 */ + ret $31,($26),1 /* .. E1 */ + +.align 3 +within_one_quad: + ldq_u $1,0($16) /* E0 */ + insql $17,$16,$2 /* E1 */ + mskql $1,$16,$4 /* E0 (after load stall) */ + bis $2,$4,$2 /* E0 */ + + mskql $2,$6,$4 /* E0 */ + mskqh $1,$6,$2 /* .. E1 */ + bis $2,$4,$1 /* E0 */ + stq_u $1,0($16) /* E0 */ + +end: + ret $31,($26),1 /* E1 */ + .end ___memset +EXPORT_SYMBOL(___memset) +EXPORT_SYMBOL(__constant_c_memset) + + .align 5 + .ent __memset16 +__memset16: + .prologue 0 + + inswl $17,0,$1 /* E0 */ + inswl $17,2,$2 /* E0 */ + inswl $17,4,$3 /* E0 */ + or $1,$2,$1 /* .. E1 */ + inswl $17,6,$4 /* E0 */ + or $1,$3,$1 /* .. E1 */ + or $1,$4,$17 /* E0 */ + br __constant_c_memset /* .. E1 */ + + .end __memset16 +EXPORT_SYMBOL(__memset16) + +memset = ___memset +__memset = ___memset + EXPORT_SYMBOL(memset) + EXPORT_SYMBOL(__memset) -- cgit v1.3.1