diff options
Diffstat (limited to 'arch/ia64/sn/kernel/setup.c')
| -rw-r--r-- | arch/ia64/sn/kernel/setup.c | 157 |
1 files changed, 153 insertions, 4 deletions
diff --git a/arch/ia64/sn/kernel/setup.c b/arch/ia64/sn/kernel/setup.c index 0fb579ef18c..e510dce9971 100644 --- a/arch/ia64/sn/kernel/setup.c +++ b/arch/ia64/sn/kernel/setup.c @@ -30,6 +30,7 @@ #include <linux/root_dev.h> #include <linux/nodemask.h> #include <linux/pm.h> +#include <linux/efi.h> #include <asm/io.h> #include <asm/sal.h> @@ -242,6 +243,135 @@ static void __init sn_check_for_wars(void) } } +/* + * Scan the EFI PCDP table (if it exists) for an acceptable VGA console + * output device. If one exists, pick it and set sn_legacy_{io,mem} to + * reflect the bus offsets needed to address it. + * + * Since pcdp support in SN is not supported in the 2.4 kernel (or at least + * the one lbs is based on) just declare the needed structs here. + * + * Reference spec http://www.dig64.org/specifications/DIG64_PCDPv20.pdf + * + * Returns 0 if no acceptable vga is found, !0 otherwise. + * + * Note: This stuff is duped here because Altix requires the PCDP to + * locate a usable VGA device due to lack of proper ACPI support. Structures + * could be used from drivers/firmware/pcdp.h, but it was decided that moving + * this file to a more public location just for Altix use was undesireable. + */ + +struct hcdp_uart_desc { + u8 pad[45]; +}; + +struct pcdp { + u8 signature[4]; /* should be 'HCDP' */ + u32 length; + u8 rev; /* should be >=3 for pcdp, <3 for hcdp */ + u8 sum; + u8 oem_id[6]; + u64 oem_tableid; + u32 oem_rev; + u32 creator_id; + u32 creator_rev; + u32 num_type0; + struct hcdp_uart_desc uart[0]; /* num_type0 of these */ + /* pcdp descriptors follow */ +} __attribute__((packed)); + +struct pcdp_device_desc { + u8 type; + u8 primary; + u16 length; + u16 index; + /* interconnect specific structure follows */ + /* device specific structure follows that */ +} __attribute__((packed)); + +struct pcdp_interface_pci { + u8 type; /* 1 == pci */ + u8 reserved; + u16 length; + u8 segment; + u8 bus; + u8 dev; + u8 fun; + u16 devid; + u16 vendid; + u32 acpi_interrupt; + u64 mmio_tra; + u64 ioport_tra; + u8 flags; + u8 translation; +} __attribute__((packed)); + +struct pcdp_vga_device { + u8 num_eas_desc; + /* ACPI Extended Address Space Desc follows */ +} __attribute__((packed)); + +/* from pcdp_device_desc.primary */ +#define PCDP_PRIMARY_CONSOLE 0x01 + +/* from pcdp_device_desc.type */ +#define PCDP_CONSOLE_INOUT 0x0 +#define PCDP_CONSOLE_DEBUG 0x1 +#define PCDP_CONSOLE_OUT 0x2 +#define PCDP_CONSOLE_IN 0x3 +#define PCDP_CONSOLE_TYPE_VGA 0x8 + +#define PCDP_CONSOLE_VGA (PCDP_CONSOLE_TYPE_VGA | PCDP_CONSOLE_OUT) + +/* from pcdp_interface_pci.type */ +#define PCDP_IF_PCI 1 + +/* from pcdp_interface_pci.translation */ +#define PCDP_PCI_TRANS_IOPORT 0x02 +#define PCDP_PCI_TRANS_MMIO 0x01 + +static void +sn_scan_pcdp(void) +{ + u8 *bp; + struct pcdp *pcdp; + struct pcdp_device_desc device; + struct pcdp_interface_pci if_pci; + extern struct efi efi; + + pcdp = efi.hcdp; + if (! pcdp) + return; /* no hcdp/pcdp table */ + + if (pcdp->rev < 3) + return; /* only support PCDP (rev >= 3) */ + + for (bp = (u8 *)&pcdp->uart[pcdp->num_type0]; + bp < (u8 *)pcdp + pcdp->length; + bp += device.length) { + memcpy(&device, bp, sizeof(device)); + if (! (device.primary & PCDP_PRIMARY_CONSOLE)) + continue; /* not primary console */ + + if (device.type != PCDP_CONSOLE_VGA) + continue; /* not VGA descriptor */ + + memcpy(&if_pci, bp+sizeof(device), sizeof(if_pci)); + if (if_pci.type != PCDP_IF_PCI) + continue; /* not PCI interconnect */ + + if (if_pci.translation & PCDP_PCI_TRANS_IOPORT) + vga_console_iobase = + if_pci.ioport_tra | __IA64_UNCACHED_OFFSET; + + if (if_pci.translation & PCDP_PCI_TRANS_MMIO) + vga_console_membase = + if_pci.mmio_tra | __IA64_UNCACHED_OFFSET; + + break; /* once we find the primary, we're done */ + } +} + /** * sn_setup - SN platform setup routine * @cmdline_p: kernel command line @@ -263,16 +393,35 @@ void __init sn_setup(char **cmdline_p) #if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE) /* - * If there was a primary vga adapter identified through the - * EFI PCDP table, make it the preferred console. Otherwise - * zero out conswitchp. + * Handle SN vga console. + * + * SN systems do not have enough ACPI table information + * being passed from prom to identify VGA adapters and the legacy + * addresses to access them. Until that is done, SN systems rely + * on the PCDP table to identify the primary VGA console if one + * exists. + * + * However, kernel PCDP support is optional, and even if it is built + * into the kernel, it will not be used if the boot cmdline contains + * console= directives. + * + * So, to work around this mess, we duplicate some of the PCDP code + * here so that the primary VGA console (as defined by PCDP) will + * work on SN systems even if a different console (e.g. serial) is + * selected on the boot line (or CONFIG_EFI_PCDP is off). */ + if (! vga_console_membase) + sn_scan_pcdp(); + if (vga_console_membase) { /* usable vga ... make tty0 the preferred default console */ - add_preferred_console("tty", 0, NULL); + if (!strstr(*cmdline_p, "console=")) + add_preferred_console("tty", 0, NULL); } else { printk(KERN_DEBUG "SGI: Disabling VGA console\n"); + if (!strstr(*cmdline_p, "console=")) + add_preferred_console("ttySG", 0, NULL); #ifdef CONFIG_DUMMY_CONSOLE conswitchp = &dummy_con; #else |