[SERIAL] default to serial console when possible

Patch from Bjorn Helgaas

This adds efi_uart_console_only() so we can default to using a serial
console if the EFI console path only contains UARTs.

diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c
index ed6bb909be0e68ac2cfc783c67aaab1905386b43..13572d153cf64bebc1af5db962ae19cc608b6e63 100644 (file)
--- a/arch/ia64/kernel/efi.c
+++ b/arch/ia64/kernel/efi.c
@@ -733,3 +733,47 @@ valid_phys_addr_range (unsigned long phys_addr, unsigned long *size)
        return 0;
 }
 
+int __init
+efi_uart_console_only(void)
+{
+       efi_status_t status;
+       char *s, name[] = "ConOut";
+       efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;
+       efi_char16_t *utf16, name_utf16[32];
+       unsigned char data[1024];
+       unsigned long size = sizeof(data);
+       struct efi_generic_dev_path *hdr, *end_addr;
+       int uart = 0;
+
+       /* Convert to UTF-16 */
+       utf16 = name_utf16;
+       s = name;
+       while (*s)
+               *utf16++ = *s++ & 0x7f;
+       *utf16 = 0;
+
+       status = efi.get_variable(name_utf16, &guid, NULL, &size, data);
+       if (status != EFI_SUCCESS) {
+               printk(KERN_ERR "No EFI %s variable?\n", name);
+               return 0;
+       }
+
+       hdr = (struct efi_generic_dev_path *) data;
+       end_addr = (struct efi_generic_dev_path *) ((u8 *) data + size);
+       while (hdr < end_addr) {
+               if (hdr->type == EFI_DEV_MSG &&
+                   hdr->sub_type == EFI_DEV_MSG_UART)
+                       uart = 1;
+               else if (hdr->type == EFI_DEV_END_PATH ||
+                         hdr->type == EFI_DEV_END_PATH2) {
+                       if (!uart)
+                               return 0;
+                       if (hdr->sub_type == EFI_DEV_END_ENTIRE)
+                               return 1;
+                       uart = 0;
+               }
+               hdr = (struct efi_generic_dev_path *) ((u8 *) hdr + hdr->length);
+       }
+       printk(KERN_ERR "Malformed %s value\n", name);
+       return 0;
+}

diff --git a/drivers/serial/8250_hcdp.c b/drivers/serial/8250_hcdp.c
index d353d917ea3b1cffc3fbf6f35ae1bf48812d5e03..e7b573f6338846284aa88771a948d12574aabf75 100644 (file)
--- a/drivers/serial/8250_hcdp.c
+++ b/drivers/serial/8250_hcdp.c
@@ -11,6 +11,7 @@
  */
 
 #include <linux/config.h>
+#include <linux/console.h>
 #include <linux/kernel.h>
 #include <linux/efi.h>
 #include <linux/init.h>
@@ -44,6 +45,7 @@ setup_serial_hcdp(void *tablep)
        unsigned long iobase;
        hcdp_t hcdp;
        int gsi, nr;
+       static char options[16];
 #if 0
        static int shift_once = 1;
 #endif
@@ -210,6 +212,12 @@ setup_serial_hcdp(void *tablep)
                        memset(&port, 0, sizeof(port));
                        continue;
                }
+
+               if (efi_uart_console_only()) {
+                       snprintf(options, sizeof(options), "%lun%d",
+                               hcdp_dev->baud, hcdp_dev->bits);
+                       add_preferred_console("ttyS", port.line, options);
+               }
                break;
        }
 

diff --git a/include/linux/efi.h b/include/linux/efi.h
index b29c8d42178f1c5ce16e92a7b20f21c226adba5f..536b82838671d08163ddaf6f2f7aaaa230fb929e 100644 (file)
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -212,6 +212,9 @@ typedef efi_status_t efi_set_virtual_address_map_t (unsigned long memory_map_siz
 #define UGA_IO_PROTOCOL_GUID \
     EFI_GUID(  0x61a4d49e, 0x6f68, 0x4f1b, 0xb9, 0x22, 0xa8, 0x6e, 0xed, 0xb, 0x7, 0xa2 )
 
+#define EFI_GLOBAL_VARIABLE_GUID \
+    EFI_GUID(  0x8be4df61, 0x93ca, 0x11d2, 0xaa, 0x0d, 0x00, 0xe0, 0x98, 0x03, 0x2b, 0x8c )
+
 typedef struct {
        efi_guid_t guid;
        unsigned long table;
@@ -294,6 +297,7 @@ extern void efi_enter_virtual_mode (void);  /* switch EFI to virtual mode, if pos
 extern u64 efi_get_iobase (void);
 extern u32 efi_mem_type (unsigned long phys_addr);
 extern u64 efi_mem_attributes (unsigned long phys_addr);
+extern int __init efi_uart_console_only (void);
 extern void efi_initialize_iomem_resources(struct resource *code_resource,
                                        struct resource *data_resource);
 extern efi_status_t phys_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc);
@@ -322,6 +326,49 @@ extern struct efi_memory_map memmap;
 #define EFI_VARIABLE_BOOTSERVICE_ACCESS 0x0000000000000002
 #define EFI_VARIABLE_RUNTIME_ACCESS     0x0000000000000004
 
+/*
+ * EFI Device Path information
+ */
+#define EFI_DEV_HW                     0x01
+#define  EFI_DEV_PCI                            1
+#define  EFI_DEV_PCCARD                                 2
+#define  EFI_DEV_MEM_MAPPED                     3
+#define  EFI_DEV_VENDOR                                 4
+#define  EFI_DEV_CONTROLLER                     5
+#define EFI_DEV_ACPI                   0x02
+#define   EFI_DEV_BASIC_ACPI                    1
+#define   EFI_DEV_EXPANDED_ACPI                         2
+#define EFI_DEV_MSG                    0x03
+#define   EFI_DEV_MSG_ATAPI                     1
+#define   EFI_DEV_MSG_SCSI                      2
+#define   EFI_DEV_MSG_FC                        3
+#define   EFI_DEV_MSG_1394                      4
+#define   EFI_DEV_MSG_USB                       5
+#define   EFI_DEV_MSG_USB_CLASS                        15
+#define   EFI_DEV_MSG_I20                       6
+#define   EFI_DEV_MSG_MAC                      11
+#define   EFI_DEV_MSG_IPV4                     12
+#define   EFI_DEV_MSG_IPV6                     13
+#define   EFI_DEV_MSG_INFINIBAND                9
+#define   EFI_DEV_MSG_UART                     14
+#define   EFI_DEV_MSG_VENDOR                   10
+#define EFI_DEV_MEDIA                  0x04
+#define   EFI_DEV_MEDIA_HARD_DRIVE              1
+#define   EFI_DEV_MEDIA_CDROM                   2
+#define   EFI_DEV_MEDIA_VENDOR                  3
+#define   EFI_DEV_MEDIA_FILE                    4
+#define   EFI_DEV_MEDIA_PROTOCOL                5
+#define EFI_DEV_BIOS_BOOT              0x05
+#define EFI_DEV_END_PATH               0x7F
+#define EFI_DEV_END_PATH2              0xFF
+#define   EFI_DEV_END_INSTANCE                 0x01
+#define   EFI_DEV_END_ENTIRE                   0xFF
+
+struct efi_generic_dev_path {
+       u8 type;
+       u8 sub_type;
+       u16 length;
+} __attribute ((packed));
 
 /*
  * efi_dir is allocated in arch/ia64/kernel/efi.c.