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/powerpc/lib/test-code-patching.c | 495 ++++++++++++++++++++++++++++++++++ 1 file changed, 495 insertions(+) create mode 100644 arch/powerpc/lib/test-code-patching.c (limited to 'arch/powerpc/lib/test-code-patching.c') diff --git a/arch/powerpc/lib/test-code-patching.c b/arch/powerpc/lib/test-code-patching.c new file mode 100644 index 000000000..1440d9963 --- /dev/null +++ b/arch/powerpc/lib/test-code-patching.c @@ -0,0 +1,495 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2008 Michael Ellerman, IBM Corporation. + */ + +#include +#include + +#include + +static int __init instr_is_branch_to_addr(const u32 *instr, unsigned long addr) +{ + if (instr_is_branch_iform(ppc_inst_read(instr)) || + instr_is_branch_bform(ppc_inst_read(instr))) + return branch_target(instr) == addr; + + return 0; +} + +static void __init test_trampoline(void) +{ + asm ("nop;nop;\n"); +} + +#define check(x) do { \ + if (!(x)) \ + pr_err("code-patching: test failed at line %d\n", __LINE__); \ +} while (0) + +static void __init test_branch_iform(void) +{ + int err; + ppc_inst_t instr; + u32 tmp[2]; + u32 *iptr = tmp; + unsigned long addr = (unsigned long)tmp; + + /* The simplest case, branch to self, no flags */ + check(instr_is_branch_iform(ppc_inst(0x48000000))); + /* All bits of target set, and flags */ + check(instr_is_branch_iform(ppc_inst(0x4bffffff))); + /* High bit of opcode set, which is wrong */ + check(!instr_is_branch_iform(ppc_inst(0xcbffffff))); + /* Middle bits of opcode set, which is wrong */ + check(!instr_is_branch_iform(ppc_inst(0x7bffffff))); + + /* Simplest case, branch to self with link */ + check(instr_is_branch_iform(ppc_inst(0x48000001))); + /* All bits of targets set */ + check(instr_is_branch_iform(ppc_inst(0x4bfffffd))); + /* Some bits of targets set */ + check(instr_is_branch_iform(ppc_inst(0x4bff00fd))); + /* Must be a valid branch to start with */ + check(!instr_is_branch_iform(ppc_inst(0x7bfffffd))); + + /* Absolute branch to 0x100 */ + ppc_inst_write(iptr, ppc_inst(0x48000103)); + check(instr_is_branch_to_addr(iptr, 0x100)); + /* Absolute branch to 0x420fc */ + ppc_inst_write(iptr, ppc_inst(0x480420ff)); + check(instr_is_branch_to_addr(iptr, 0x420fc)); + /* Maximum positive relative branch, + 20MB - 4B */ + ppc_inst_write(iptr, ppc_inst(0x49fffffc)); + check(instr_is_branch_to_addr(iptr, addr + 0x1FFFFFC)); + /* Smallest negative relative branch, - 4B */ + ppc_inst_write(iptr, ppc_inst(0x4bfffffc)); + check(instr_is_branch_to_addr(iptr, addr - 4)); + /* Largest negative relative branch, - 32 MB */ + ppc_inst_write(iptr, ppc_inst(0x4a000000)); + check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); + + /* Branch to self, with link */ + err = create_branch(&instr, iptr, addr, BRANCH_SET_LINK); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); + + /* Branch to self - 0x100, with link */ + err = create_branch(&instr, iptr, addr - 0x100, BRANCH_SET_LINK); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x100)); + + /* Branch to self + 0x100, no link */ + err = create_branch(&instr, iptr, addr + 0x100, 0); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr + 0x100)); + + /* Maximum relative negative offset, - 32 MB */ + err = create_branch(&instr, iptr, addr - 0x2000000, BRANCH_SET_LINK); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); + + /* Out of range relative negative offset, - 32 MB + 4*/ + err = create_branch(&instr, iptr, addr - 0x2000004, BRANCH_SET_LINK); + check(err); + + /* Out of range relative positive offset, + 32 MB */ + err = create_branch(&instr, iptr, addr + 0x2000000, BRANCH_SET_LINK); + check(err); + + /* Unaligned target */ + err = create_branch(&instr, iptr, addr + 3, BRANCH_SET_LINK); + check(err); + + /* Check flags are masked correctly */ + err = create_branch(&instr, iptr, addr, 0xFFFFFFFC); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); + check(ppc_inst_equal(instr, ppc_inst(0x48000000))); +} + +static void __init test_create_function_call(void) +{ + u32 *iptr; + unsigned long dest; + ppc_inst_t instr; + + /* Check we can create a function call */ + iptr = (u32 *)ppc_function_entry(test_trampoline); + dest = ppc_function_entry(test_create_function_call); + create_branch(&instr, iptr, dest, BRANCH_SET_LINK); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, dest)); +} + +static void __init test_branch_bform(void) +{ + int err; + unsigned long addr; + ppc_inst_t instr; + u32 tmp[2]; + u32 *iptr = tmp; + unsigned int flags; + + addr = (unsigned long)iptr; + + /* The simplest case, branch to self, no flags */ + check(instr_is_branch_bform(ppc_inst(0x40000000))); + /* All bits of target set, and flags */ + check(instr_is_branch_bform(ppc_inst(0x43ffffff))); + /* High bit of opcode set, which is wrong */ + check(!instr_is_branch_bform(ppc_inst(0xc3ffffff))); + /* Middle bits of opcode set, which is wrong */ + check(!instr_is_branch_bform(ppc_inst(0x7bffffff))); + + /* Absolute conditional branch to 0x100 */ + ppc_inst_write(iptr, ppc_inst(0x43ff0103)); + check(instr_is_branch_to_addr(iptr, 0x100)); + /* Absolute conditional branch to 0x20fc */ + ppc_inst_write(iptr, ppc_inst(0x43ff20ff)); + check(instr_is_branch_to_addr(iptr, 0x20fc)); + /* Maximum positive relative conditional branch, + 32 KB - 4B */ + ppc_inst_write(iptr, ppc_inst(0x43ff7ffc)); + check(instr_is_branch_to_addr(iptr, addr + 0x7FFC)); + /* Smallest negative relative conditional branch, - 4B */ + ppc_inst_write(iptr, ppc_inst(0x43fffffc)); + check(instr_is_branch_to_addr(iptr, addr - 4)); + /* Largest negative relative conditional branch, - 32 KB */ + ppc_inst_write(iptr, ppc_inst(0x43ff8000)); + check(instr_is_branch_to_addr(iptr, addr - 0x8000)); + + /* All condition code bits set & link */ + flags = 0x3ff000 | BRANCH_SET_LINK; + + /* Branch to self */ + err = create_cond_branch(&instr, iptr, addr, flags); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); + + /* Branch to self - 0x100 */ + err = create_cond_branch(&instr, iptr, addr - 0x100, flags); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x100)); + + /* Branch to self + 0x100 */ + err = create_cond_branch(&instr, iptr, addr + 0x100, flags); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr + 0x100)); + + /* Maximum relative negative offset, - 32 KB */ + err = create_cond_branch(&instr, iptr, addr - 0x8000, flags); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x8000)); + + /* Out of range relative negative offset, - 32 KB + 4*/ + err = create_cond_branch(&instr, iptr, addr - 0x8004, flags); + check(err); + + /* Out of range relative positive offset, + 32 KB */ + err = create_cond_branch(&instr, iptr, addr + 0x8000, flags); + check(err); + + /* Unaligned target */ + err = create_cond_branch(&instr, iptr, addr + 3, flags); + check(err); + + /* Check flags are masked correctly */ + err = create_cond_branch(&instr, iptr, addr, 0xFFFFFFFC); + ppc_inst_write(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); + check(ppc_inst_equal(instr, ppc_inst(0x43FF0000))); +} + +static void __init test_translate_branch(void) +{ + unsigned long addr; + void *p, *q; + ppc_inst_t instr; + void *buf; + + buf = vmalloc(PAGE_ALIGN(0x2000000 + 1)); + check(buf); + if (!buf) + return; + + /* Simple case, branch to self moved a little */ + p = buf; + addr = (unsigned long)p; + create_branch(&instr, p, addr, 0); + ppc_inst_write(p, instr); + check(instr_is_branch_to_addr(p, addr)); + q = p + 4; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(q, addr)); + + /* Maximum negative case, move b . to addr + 32 MB */ + p = buf; + addr = (unsigned long)p; + create_branch(&instr, p, addr, 0); + ppc_inst_write(p, instr); + q = buf + 0x2000000; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x4a000000))); + + /* Maximum positive case, move x to x - 32 MB + 4 */ + p = buf + 0x2000000; + addr = (unsigned long)p; + create_branch(&instr, p, addr, 0); + ppc_inst_write(p, instr); + q = buf + 4; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x49fffffc))); + + /* Jump to x + 16 MB moved to x + 20 MB */ + p = buf; + addr = 0x1000000 + (unsigned long)buf; + create_branch(&instr, p, addr, BRANCH_SET_LINK); + ppc_inst_write(p, instr); + q = buf + 0x1400000; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + + /* Jump to x + 16 MB moved to x - 16 MB + 4 */ + p = buf + 0x1000000; + addr = 0x2000000 + (unsigned long)buf; + create_branch(&instr, p, addr, 0); + ppc_inst_write(p, instr); + q = buf + 4; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + + + /* Conditional branch tests */ + + /* Simple case, branch to self moved a little */ + p = buf; + addr = (unsigned long)p; + create_cond_branch(&instr, p, addr, 0); + ppc_inst_write(p, instr); + check(instr_is_branch_to_addr(p, addr)); + q = buf + 4; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(q, addr)); + + /* Maximum negative case, move b . to addr + 32 KB */ + p = buf; + addr = (unsigned long)p; + create_cond_branch(&instr, p, addr, 0xFFFFFFFC); + ppc_inst_write(p, instr); + q = buf + 0x8000; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff8000))); + + /* Maximum positive case, move x to x - 32 KB + 4 */ + p = buf + 0x8000; + addr = (unsigned long)p; + create_cond_branch(&instr, p, addr, 0xFFFFFFFC); + ppc_inst_write(p, instr); + q = buf + 4; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff7ffc))); + + /* Jump to x + 12 KB moved to x + 20 KB */ + p = buf; + addr = 0x3000 + (unsigned long)buf; + create_cond_branch(&instr, p, addr, BRANCH_SET_LINK); + ppc_inst_write(p, instr); + q = buf + 0x5000; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + + /* Jump to x + 8 KB moved to x - 8 KB + 4 */ + p = buf + 0x2000; + addr = 0x4000 + (unsigned long)buf; + create_cond_branch(&instr, p, addr, 0); + ppc_inst_write(p, instr); + q = buf + 4; + translate_branch(&instr, q, p); + ppc_inst_write(q, instr); + check(instr_is_branch_to_addr(p, addr)); + check(instr_is_branch_to_addr(q, addr)); + + /* Free the buffer we were using */ + vfree(buf); +} + +static void __init test_prefixed_patching(void) +{ + u32 *iptr = (u32 *)ppc_function_entry(test_trampoline); + u32 expected[2] = {OP_PREFIX << 26, 0}; + ppc_inst_t inst = ppc_inst_prefix(OP_PREFIX << 26, 0); + + if (!IS_ENABLED(CONFIG_PPC64)) + return; + + patch_instruction(iptr, inst); + + check(!memcmp(iptr, expected, sizeof(expected))); +} + +static void __init test_multi_instruction_patching(void) +{ + u32 code[32]; + void *buf; + u32 *addr32; + u64 *addr64; + ppc_inst_t inst64 = ppc_inst_prefix(OP_PREFIX << 26 | 3UL << 24, PPC_RAW_TRAP()); + u32 inst32 = PPC_RAW_NOP(); + + buf = vzalloc(PAGE_SIZE * 8); + check(buf); + if (!buf) + return; + + /* Test single page 32-bit repeated instruction */ + addr32 = buf + PAGE_SIZE; + check(!patch_instructions(addr32 + 1, &inst32, 12, true)); + + check(addr32[0] == 0); + check(addr32[1] == inst32); + check(addr32[2] == inst32); + check(addr32[3] == inst32); + check(addr32[4] == 0); + + /* Test single page 64-bit repeated instruction */ + if (IS_ENABLED(CONFIG_PPC64)) { + check(ppc_inst_prefixed(inst64)); + + addr64 = buf + PAGE_SIZE * 2; + ppc_inst_write(code, inst64); + check(!patch_instructions((u32 *)(addr64 + 1), code, 24, true)); + + check(addr64[0] == 0); + check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[1]), inst64)); + check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[2]), inst64)); + check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[3]), inst64)); + check(addr64[4] == 0); + } + + /* Test single page memcpy */ + addr32 = buf + PAGE_SIZE * 3; + + for (int i = 0; i < ARRAY_SIZE(code); i++) + code[i] = i + 1; + + check(!patch_instructions(addr32 + 1, code, sizeof(code), false)); + + check(addr32[0] == 0); + check(!memcmp(&addr32[1], code, sizeof(code))); + check(addr32[ARRAY_SIZE(code) + 1] == 0); + + /* Test multipage 32-bit repeated instruction */ + addr32 = buf + PAGE_SIZE * 4 - 8; + check(!patch_instructions(addr32 + 1, &inst32, 12, true)); + + check(addr32[0] == 0); + check(addr32[1] == inst32); + check(addr32[2] == inst32); + check(addr32[3] == inst32); + check(addr32[4] == 0); + + /* Test multipage 64-bit repeated instruction */ + if (IS_ENABLED(CONFIG_PPC64)) { + check(ppc_inst_prefixed(inst64)); + + addr64 = buf + PAGE_SIZE * 5 - 8; + ppc_inst_write(code, inst64); + check(!patch_instructions((u32 *)(addr64 + 1), code, 24, true)); + + check(addr64[0] == 0); + check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[1]), inst64)); + check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[2]), inst64)); + check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[3]), inst64)); + check(addr64[4] == 0); + } + + /* Test multipage memcpy */ + addr32 = buf + PAGE_SIZE * 6 - 12; + + for (int i = 0; i < ARRAY_SIZE(code); i++) + code[i] = i + 1; + + check(!patch_instructions(addr32 + 1, code, sizeof(code), false)); + + check(addr32[0] == 0); + check(!memcmp(&addr32[1], code, sizeof(code))); + check(addr32[ARRAY_SIZE(code) + 1] == 0); + + vfree(buf); +} + +static void __init test_data_patching(void) +{ + void *buf; + u32 *addr32; + + buf = vzalloc(PAGE_SIZE); + check(buf); + if (!buf) + return; + + addr32 = buf + 128; + + addr32[1] = 0xA0A1A2A3; + addr32[2] = 0xB0B1B2B3; + + check(!patch_uint(&addr32[1], 0xC0C1C2C3)); + + check(addr32[0] == 0); + check(addr32[1] == 0xC0C1C2C3); + check(addr32[2] == 0xB0B1B2B3); + check(addr32[3] == 0); + + /* Unaligned patch_ulong() should fail */ + if (IS_ENABLED(CONFIG_PPC64)) + check(patch_ulong(&addr32[1], 0xD0D1D2D3) == -EINVAL); + + check(!patch_ulong(&addr32[2], 0xD0D1D2D3)); + + check(addr32[0] == 0); + check(addr32[1] == 0xC0C1C2C3); + check(*(unsigned long *)(&addr32[2]) == 0xD0D1D2D3); + + if (!IS_ENABLED(CONFIG_PPC64)) + check(addr32[3] == 0); + + check(addr32[4] == 0); + + vfree(buf); +} + +static int __init test_code_patching(void) +{ + pr_info("Running code patching self-tests ...\n"); + + test_branch_iform(); + test_branch_bform(); + test_create_function_call(); + test_translate_branch(); + test_prefixed_patching(); + test_multi_instruction_patching(); + test_data_patching(); + + return 0; +} +late_initcall(test_code_patching); 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