On Wed, 3 Dec 2025 00:28:22 +0800 Zhao Liu <zhao1.liu@intel.com> wrote:
From: Philippe Mathieu-Daudé <philmd@linaro.org>
Now all calls of x86 machines to fw_cfg_init_io_dma() pass DMA arguments, so the FWCfgState (FWCfgIoState) created by x86 machines enables DMA by default.
Although other callers of fw_cfg_init_io_dma() besides x86 also pass DMA arguments to create DMA-enabled FwCfgIoState, the "dma_enabled" property of FwCfgIoState cannot yet be removed, because Sun4u and Sun4v still create DMA-disabled FwCfgIoState (bypass fw_cfg_init_io_dma()) in sun4uv_init() (hw/sparc64/sun4u.c).
Maybe reusing fw_cfg_init_io_dma() for them would be a better choice, or adding fw_cfg_init_io_nodma(). However, before that, first simplify the handling of FwCfgState in x86.
Considering that FwCfgIoState in x86 enables DMA by default, remove the handling for DMA-disabled cases and replace DMA checks with assertions to ensure that the default DMA-enabled setting is not broken.
Then 'linuxboot.bin' isn't used anymore, and it will be removed in the next commit.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Zhao Liu <zhao1.liu@intel.com> --- Changes since v4: * Keep "dma_enabled" property in fw_cfg_io_properties[]. * Replace DMA checks with assertions for x86 machines. --- hw/i386/fw_cfg.c | 16 ++++++++-------- hw/i386/x86-common.c | 6 ++---- 2 files changed, 10 insertions(+), 12 deletions(-)
diff --git a/hw/i386/fw_cfg.c b/hw/i386/fw_cfg.c index 5c0bcd5f8a9f..5670e8553eaa 100644 --- a/hw/i386/fw_cfg.c +++ b/hw/i386/fw_cfg.c @@ -215,18 +215,18 @@ void fw_cfg_build_feature_control(MachineState *ms, FWCfgState *fw_cfg) #ifdef CONFIG_ACPI void fw_cfg_add_acpi_dsdt(Aml *scope, FWCfgState *fw_cfg) { + uint8_t io_size; + Aml *dev = aml_device("FWCF"); + Aml *crs = aml_resource_template(); + /* * when using port i/o, the 8-bit data register *always* overlaps * with half of the 16-bit control register. Hence, the total size - * of the i/o region used is FW_CFG_CTL_SIZE; when using DMA, the - * DMA control register is located at FW_CFG_DMA_IO_BASE + 4 + * of the i/o region used is FW_CFG_CTL_SIZE; And the DMA control + * register is located at FW_CFG_DMA_IO_BASE + 4 */ - Object *obj = OBJECT(fw_cfg); - uint8_t io_size = object_property_get_bool(obj, "dma_enabled", NULL) ? - ROUND_UP(FW_CFG_CTL_SIZE, 4) + sizeof(dma_addr_t) : - FW_CFG_CTL_SIZE; - Aml *dev = aml_device("FWCF"); - Aml *crs = aml_resource_template(); + assert(fw_cfg_dma_enabled(fw_cfg));
this was supposed to be machine agnostic, but given that it only used by x86 it shouldn't cause issues, so Acked-by: Igor Mammedov <imammedo@redhat.com>
+ io_size = ROUND_UP(FW_CFG_CTL_SIZE, 4) + sizeof(dma_addr_t);
aml_append(dev, aml_name_decl("_HID", aml_string("QEMU0002")));
diff --git a/hw/i386/x86-common.c b/hw/i386/x86-common.c index 1ee55382dab8..e8dc4d903bd6 100644 --- a/hw/i386/x86-common.c +++ b/hw/i386/x86-common.c @@ -1002,10 +1002,8 @@ void x86_load_linux(X86MachineState *x86ms, }
option_rom[nb_option_roms].bootindex = 0; - option_rom[nb_option_roms].name = "linuxboot.bin"; - if (fw_cfg_dma_enabled(fw_cfg)) { - option_rom[nb_option_roms].name = "linuxboot_dma.bin"; - } + assert(fw_cfg_dma_enabled(fw_cfg)); + option_rom[nb_option_roms].name = "linuxboot_dma.bin"; nb_option_roms++; }