drivers/serial/8250_hcdp.c

   1 /*
   2  * linux/drivers/char/hcdp_serial.c
   3  *
   4  * Copyright (C) 2002 Hewlett-Packard Co.
   5  *      Khalid Aziz <khalid_aziz@hp.com>
   6  *
   7  * Parse the EFI HCDP table to locate serial console and debug ports and
   8  * initialize them.
   9  *
  10  * 2002/08/29 davidm    Adjust it to new 2.5 serial driver infrastructure.
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/kernel.h>
  15 #include <linux/efi.h>
  16 #include <linux/init.h>
  17 #include <linux/tty.h>
  18 #include <linux/serial.h>
  19 #include <linux/serial_core.h>
  20 #include <linux/types.h>
  21 #include <linux/acpi.h>
  22
  23 #include <asm/io.h>
  24 #include <asm/serial.h>
  25 #include <asm/acpi.h>
  26
  27 #include "8250_hcdp.h"
  28
  29 #undef SERIAL_DEBUG_HCDP
  30
  31 /*
  32  * Parse the HCDP table to find descriptions for headless console and debug
  33  * serial ports and add them to rs_table[]. A pointer to HCDP table is
  34  * passed as parameter. This function should be called before
  35  * serial_console_init() is called to make sure the HCDP serial console will
  36  * be available for use. IA-64 kernel calls this function from setup_arch()
  37  * after the EFI and ACPI tables have been parsed.
  38  */
  39 void __init
  40 setup_serial_hcdp(void *tablep)
  41 {
  42         hcdp_dev_t *hcdp_dev;
  43         struct uart_port port;
  44         unsigned long iobase;
  45         hcdp_t hcdp;
  46         int gsi, nr;
  47 #if 0
  48         static int shift_once = 1;
  49 #endif
  50
  51 #ifdef SERIAL_DEBUG_HCDP
  52         printk("Entering setup_serial_hcdp()\n");
  53 #endif
  54
  55         /* Verify we have a valid table pointer */
  56         if (!tablep)
  57                 return;
  58
  59         memset(&port, 0, sizeof(port));
  60
  61         /*
  62          * Don't trust firmware to give us a table starting at an aligned
  63          * address. Make a local copy of the HCDP table with aligned
  64          * structures.
  65          */
  66         memcpy(&hcdp, tablep, sizeof(hcdp));
  67
  68         /*
  69          * Perform a sanity check on the table. Table should have a signature
  70          * of "HCDP" and it should be atleast 82 bytes long to have any
  71          * useful information.
  72          */
  73         if ((strncmp(hcdp.signature, HCDP_SIGNATURE, HCDP_SIG_LEN) != 0))
  74                 return;
  75         if (hcdp.len < 82)
  76                 return;
  77
  78 #ifdef SERIAL_DEBUG_HCDP
  79         printk("setup_serial_hcdp(): table pointer = 0x%p, sig = '%.4s'\n",
  80                tablep, hcdp.signature);
  81         printk(" length = %d, rev = %d, ", hcdp.len, hcdp.rev);
  82         printk("OEM ID = %.6s, # of entries = %d\n", hcdp.oemid,
  83                         hcdp.num_entries);
  84 #endif
  85
  86         /*
  87          * Parse each device entry
  88          */
  89         for (nr = 0; nr < hcdp.num_entries; nr++) {
  90                 hcdp_dev = hcdp.hcdp_dev + nr;
  91                 /*
  92                  * We will parse only the primary console device which is
  93                  * the first entry for these devices. We will ignore rest
  94                  * of the entries for the same type device that has already
  95                  * been parsed and initialized
  96                  */
  97                 if (hcdp_dev->type != HCDP_DEV_CONSOLE)
  98                         continue;
  99
 100                 iobase = ((u64) hcdp_dev->base_addr.addrhi << 32) |
 101                                         hcdp_dev->base_addr.addrlo;
 102                 gsi = hcdp_dev->global_int;
 103
 104                 /* See PCI spec v2.2, Appendix D (Class Codes): */
 105                 switch (hcdp_dev->pci_prog_intfc) {
 106                 case 0x00:
 107                         port.type = PORT_8250;
 108                         break;
 109                 case 0x01:
 110                         port.type = PORT_16450;
 111                         break;
 112                 case 0x02:
 113                         port.type = PORT_16550;
 114                         break;
 115                 case 0x03:
 116                         port.type = PORT_16650;
 117                         break;
 118                 case 0x04:
 119                         port.type = PORT_16750;
 120                         break;
 121                 case 0x05:
 122                         port.type = PORT_16850;
 123                         break;
 124                 case 0x06:
 125                         port.type = PORT_16C950;
 126                         break;
 127                 default:
 128                         printk(KERN_WARNING "warning: EFI HCDP table reports "
 129                                 "unknown serial programming interface 0x%02x; "
 130                                 "will autoprobe.\n", hcdp_dev->pci_prog_intfc);
 131                         port.type = PORT_UNKNOWN;
 132                         break;
 133                 }
 134
 135 #ifdef SERIAL_DEBUG_HCDP
 136                 printk("  type = %s, uart = %d\n",
 137                         ((hcdp_dev->type == HCDP_DEV_CONSOLE) ?
 138                         "Headless Console" :
 139                         ((hcdp_dev->type == HCDP_DEV_DEBUG) ?
 140                         "Debug port" : "Huh????")), port.type);
 141                 printk("  base address space = %s, base address = 0x%lx\n",
 142                        ((hcdp_dev->base_addr.space_id == ACPI_MEM_SPACE) ?
 143                        "Memory Space" :
 144                         ((hcdp_dev->base_addr.space_id == ACPI_IO_SPACE) ?
 145                         "I/O space" : "PCI space")),
 146                        iobase);
 147                 printk("  gsi = %d, baud rate = %lu, bits = %d, clock = %d\n",
 148                        gsi, (unsigned long) hcdp_dev->baud, hcdp_dev->bits,
 149                        hcdp_dev->clock_rate);
 150                 if (hcdp_dev->base_addr.space_id == ACPI_PCICONF_SPACE)
 151                         printk(" PCI id: %02x:%02x:%02x, vendor ID=0x%x, "
 152                                 "dev ID=0x%x\n", hcdp_dev->pci_seg,
 153                                 hcdp_dev->pci_bus, hcdp_dev->pci_dev,
 154                                 hcdp_dev->pci_vendor_id, hcdp_dev->pci_dev_id);
 155 #endif
 156                 /*
 157                  * Now fill in a port structure to update the 8250 port table..
 158                  */
 159                 if (hcdp_dev->clock_rate)
 160                         port.uartclk = hcdp_dev->clock_rate;
 161                 else
 162                         port.uartclk = BASE_BAUD * 16;
 163
 164                 /*
 165                  * Check if this is an I/O mapped address or a memory mapped
 166                  * address
 167                  */
 168                 if (hcdp_dev->base_addr.space_id == ACPI_MEM_SPACE) {
 169                         port.iobase = 0;
 170                         port.mapbase = iobase;
 171                         port.membase = ioremap(iobase, 64);
 172                         port.iotype = SERIAL_IO_MEM;
 173                 } else if (hcdp_dev->base_addr.space_id == ACPI_IO_SPACE) {
 174                         port.iobase = iobase;
 175                         port.mapbase = 0;
 176                         port.membase = NULL;
 177                         port.iotype = SERIAL_IO_PORT;
 178                 } else if (hcdp_dev->base_addr.space_id == ACPI_PCICONF_SPACE) {
 179                         printk(KERN_WARNING"warning: No support for PCI serial console\n");
 180                         return;
 181                 }
 182 #ifdef CONFIG_IA64
 183                 port.irq = acpi_register_irq(gsi, ACPI_ACTIVE_HIGH,
 184                                 ACPI_EDGE_SENSITIVE);
 185 #else
 186                 port.irq = gsi;
 187 #endif
 188                 port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
 189                 if (gsi)
 190                         port.flags |= ASYNC_AUTO_IRQ;
 191
 192                 /*
 193                  * Note: the above memset() initializes port.line to 0,
 194                  * so we register this port as ttyS0.
 195                  */
 196                 if (early_serial_setup(&port) < 0) {
 197                         printk("setup_serial_hcdp(): early_serial_setup() "
 198                                 "for HCDP serial console port failed. "
 199                                 "Will try any additional consoles in HCDP.\n");
 200                         continue;
 201                 }
 202                 break;
 203         }
 204
 205 #ifdef SERIAL_DEBUG_HCDP
 206         printk("Leaving setup_serial_hcdp()\n");
 207 #endif
 208 }
 209
 210 #ifdef CONFIG_IA64_EARLY_PRINTK_UART
 211 unsigned long
 212 hcdp_early_uart (void)
 213 {
 214         efi_system_table_t *systab;
 215         efi_config_table_t *config_tables;
 216         unsigned long addr = 0;
 217         hcdp_t *hcdp = 0;
 218         hcdp_dev_t *dev;
 219         int i;
 220
 221         systab = (efi_system_table_t *) ia64_boot_param->efi_systab;
 222         if (!systab)
 223                 return 0;
 224         systab = __va(systab);
 225
 226         config_tables = (efi_config_table_t *) systab->tables;
 227         if (!config_tables)
 228                 return 0;
 229         config_tables = __va(config_tables);
 230
 231         for (i = 0; i < systab->nr_tables; i++) {
 232                 if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
 233                         hcdp = (hcdp_t *) config_tables[i].table;
 234                         break;
 235                 }
 236         }
 237         if (!hcdp)
 238                 return 0;
 239         hcdp = __va(hcdp);
 240
 241         for (i = 0, dev = hcdp->hcdp_dev; i < hcdp->num_entries; i++, dev++) {
 242                 if (dev->type == HCDP_DEV_CONSOLE) {
 243                         addr = (u64) dev->base_addr.addrhi << 32 | dev->base_addr.addrlo;
 244                         break;
 245                 }
 246         }
 247         return addr;
 248 }
 249 #endif /* CONFIG_IA64_EARLY_PRINTK_UART */