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) --- drivers/acpi/riscv/cppc.c | 155 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 drivers/acpi/riscv/cppc.c (limited to 'drivers/acpi/riscv/cppc.c') diff --git a/drivers/acpi/riscv/cppc.c b/drivers/acpi/riscv/cppc.c new file mode 100644 index 000000000..42c1a9052 --- /dev/null +++ b/drivers/acpi/riscv/cppc.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Implement CPPC FFH helper routines for RISC-V. + * + * Copyright (C) 2024 Ventana Micro Systems Inc. + */ + +#include +#include +#include + +#define SBI_EXT_CPPC 0x43505043 + +/* CPPC interfaces defined in SBI spec */ +#define SBI_CPPC_PROBE 0x0 +#define SBI_CPPC_READ 0x1 +#define SBI_CPPC_READ_HI 0x2 +#define SBI_CPPC_WRITE 0x3 + +/* RISC-V FFH definitions from RISC-V FFH spec */ +#define FFH_CPPC_TYPE(r) (((r) & GENMASK_ULL(63, 60)) >> 60) +#define FFH_CPPC_SBI_REG(r) ((r) & GENMASK(31, 0)) +#define FFH_CPPC_CSR_NUM(r) ((r) & GENMASK(11, 0)) + +#define FFH_CPPC_SBI 0x1 +#define FFH_CPPC_CSR 0x2 + +struct sbi_cppc_data { + u64 val; + u32 reg; + struct sbiret ret; +}; + +static bool cppc_ext_present; + +static int __init sbi_cppc_init(void) +{ + if (sbi_spec_version >= sbi_mk_version(2, 0) && + sbi_probe_extension(SBI_EXT_CPPC) > 0) { + cppc_ext_present = true; + } else { + cppc_ext_present = false; + } + + return 0; +} +device_initcall(sbi_cppc_init); + +static void sbi_cppc_read(void *read_data) +{ + struct sbi_cppc_data *data = (struct sbi_cppc_data *)read_data; + + data->ret = sbi_ecall(SBI_EXT_CPPC, SBI_CPPC_READ, + data->reg, 0, 0, 0, 0, 0); +} + +static void sbi_cppc_write(void *write_data) +{ + struct sbi_cppc_data *data = (struct sbi_cppc_data *)write_data; + + data->ret = sbi_ecall(SBI_EXT_CPPC, SBI_CPPC_WRITE, + data->reg, data->val, 0, 0, 0, 0); +} + +static void cppc_ffh_csr_read(void *read_data) +{ + struct sbi_cppc_data *data = (struct sbi_cppc_data *)read_data; + + switch (data->reg) { + /* Support only TIME CSR for now */ + case CSR_TIME: + data->ret.value = csr_read(CSR_TIME); + data->ret.error = 0; + break; + default: + data->ret.error = -EINVAL; + break; + } +} + +static void cppc_ffh_csr_write(void *write_data) +{ + struct sbi_cppc_data *data = (struct sbi_cppc_data *)write_data; + + data->ret.error = -EINVAL; +} + +/* + * Refer to drivers/acpi/cppc_acpi.c for the description of the functions + * below. + */ +bool cpc_ffh_supported(void) +{ + return true; +} + +int cpc_read_ffh(int cpu, struct cpc_reg *reg, u64 *val) +{ + struct sbi_cppc_data data; + + if (WARN_ON_ONCE(irqs_disabled())) + return -EPERM; + + if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_SBI) { + if (!cppc_ext_present) + return -EINVAL; + + data.reg = FFH_CPPC_SBI_REG(reg->address); + + smp_call_function_single(cpu, sbi_cppc_read, &data, 1); + + *val = data.ret.value; + + return (data.ret.error) ? sbi_err_map_linux_errno(data.ret.error) : 0; + } else if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_CSR) { + data.reg = FFH_CPPC_CSR_NUM(reg->address); + + smp_call_function_single(cpu, cppc_ffh_csr_read, &data, 1); + + *val = data.ret.value; + + return data.ret.error; + } + + return -EINVAL; +} + +int cpc_write_ffh(int cpu, struct cpc_reg *reg, u64 val) +{ + struct sbi_cppc_data data; + + if (WARN_ON_ONCE(irqs_disabled())) + return -EPERM; + + if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_SBI) { + if (!cppc_ext_present) + return -EINVAL; + + data.reg = FFH_CPPC_SBI_REG(reg->address); + data.val = val; + + smp_call_function_single(cpu, sbi_cppc_write, &data, 1); + + return (data.ret.error) ? sbi_err_map_linux_errno(data.ret.error) : 0; + } else if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_CSR) { + data.reg = FFH_CPPC_CSR_NUM(reg->address); + data.val = val; + + smp_call_function_single(cpu, cppc_ffh_csr_write, &data, 1); + + return data.ret.error; + } + + return -EINVAL; +} -- cgit v1.3.1