From: Andy Shevchenko Date: Thu, 15 Nov 2018 18:06:33 +0200 Subject: [U-Boot] [PATCH v1 2/2] WIP: x86: acpi: Generate SPCR table In-Reply-To: References: <20180922130505.77474-1-andriy.shevchenko@linux.intel.com> <20180922130505.77474-3-andriy.shevchenko@linux.intel.com> Message-ID: <20181115160633.GU10650@smile.fi.intel.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Tue, Sep 25, 2018 at 10:27:33AM +0800, Bin Meng wrote: > On Sat, Sep 22, 2018 at 9:05 PM Andy Shevchenko > wrote: > > +/* SPCR (Serial Port Console Redirection table) */ > > +struct __packed acpi_spcr { > > + struct acpi_table_header header; /* Common ACPI table header */ > > + u8 interface_type; /* 0=full 16550, 1=subset of 16550 */ > > + u8 reserved[3]; > > + struct acpi_gen_regaddr serial_port; /* The base address of the Serial Port register set */ > > + u8 interrupt_type; > > + u8 pc_interrupt; > > + u32 interrupt; /* Global system interrupt */ > > + u8 baud_rate; > > + u8 parity; > > + u8 stop_bits; > > + u8 flow_control; > > + u8 terminal_type; > > + u8 reserved1; > > + u16 pci_device_id; /* Must be 0xffff if not PCI device */ > > + u16 pci_vendor_id; /* Must be 0xffff if not PCI device */ > > + u8 pci_bus; > > + u8 pci_device; > > + u8 pci_function; > > + u32 pci_flags; > > + u8 pci_segment; > > + u32 reserved2; > > +}; > I see not every member of 'struct __packed acpi_spcr' is populated. > Are they not used by kernel? If kernel does not use it, it is used by > Windows? No idea about Windows, but there are two statements: - *not all* should be filled, otherwise it would be contradictory (PCI vs. non-PCI device, for example) - Linux doesn't use all of them, indeed -- With Best Regards, Andy Shevchenko