drivers/pci/hotplug/shpchprm_acpi.c

   1 /*
   2  * SHPCHPRM ACPI: PHP Resource Manager for ACPI platform
   3  *
   4  * Copyright (C) 2003-2004 Intel Corporation
   5  *
   6  * All rights reserved.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or (at
  11  * your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  16  * NON INFRINGEMENT.  See the GNU General Public License for more
  17  * details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  *
  23  * Send feedback to <kristen.c.accardi@intel.com>
  24  *
  25  */
  26
  27 #include <linux/config.h>
  28 #include <linux/module.h>
  29 #include <linux/kernel.h>
  30 #include <linux/types.h>
  31 #include <linux/pci.h>
  32 #include <linux/init.h>
  33 #include <linux/acpi.h>
  34 #include <linux/efi.h>
  35 #include <asm/uaccess.h>
  36 #include <asm/system.h>
  37 #include <acpi/acpi.h>
  38 #include <acpi/acpi_bus.h>
  39 #include <acpi/actypes.h>
  40 #include "shpchp.h"
  41
  42 #define METHOD_NAME__SUN        "_SUN"
  43 #define METHOD_NAME__HPP        "_HPP"
  44 #define METHOD_NAME_OSHP        "OSHP"
  45
  46 static u8 * acpi_path_name( acpi_handle handle)
  47 {
  48         acpi_status             status;
  49         static u8       path_name[ACPI_PATHNAME_MAX];
  50         struct acpi_buffer              ret_buf = { ACPI_PATHNAME_MAX, path_name };
  51
  52         memset(path_name, 0, sizeof (path_name));
  53         status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &ret_buf);
  54
  55         if (ACPI_FAILURE(status))
  56                 return NULL;
  57         else
  58                 return path_name;
  59 }
  60
  61 static acpi_status
  62 acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
  63 {
  64         acpi_status             status;
  65         u8                      nui[4];
  66         struct acpi_buffer      ret_buf = { 0, NULL};
  67         union acpi_object       *ext_obj, *package;
  68         u8                      *path_name = acpi_path_name(handle);
  69         int                     i, len = 0;
  70
  71         /* get _hpp */
  72         status = acpi_evaluate_object(handle, METHOD_NAME__HPP, NULL, &ret_buf);
  73         switch (status) {
  74         case AE_BUFFER_OVERFLOW:
  75                 ret_buf.pointer = kmalloc (ret_buf.length, GFP_KERNEL);
  76                 if (!ret_buf.pointer) {
  77                         err ("%s:%s alloc for _HPP fail\n", __FUNCTION__,
  78                                         path_name);
  79                         return AE_NO_MEMORY;
  80                 }
  81                 status = acpi_evaluate_object(handle, METHOD_NAME__HPP,
  82                                 NULL, &ret_buf);
  83                 if (ACPI_SUCCESS(status))
  84                         break;
  85         default:
  86                 if (ACPI_FAILURE(status)) {
  87                         dbg("%s:%s _HPP fail=0x%x\n", __FUNCTION__,
  88                                         path_name, status);
  89                         return status;
  90                 }
  91         }
  92
  93         ext_obj = (union acpi_object *) ret_buf.pointer;
  94         if (ext_obj->type != ACPI_TYPE_PACKAGE) {
  95                 err ("%s:%s _HPP obj not a package\n", __FUNCTION__,
  96                                 path_name);
  97                 status = AE_ERROR;
  98                 goto free_and_return;
  99         }
 100
 101         len = ext_obj->package.count;
 102         package = (union acpi_object *) ret_buf.pointer;
 103         for ( i = 0; (i < len) || (i < 4); i++) {
 104                 ext_obj = (union acpi_object *) &package->package.elements[i];
 105                 switch (ext_obj->type) {
 106                 case ACPI_TYPE_INTEGER:
 107                         nui[i] = (u8)ext_obj->integer.value;
 108                         break;
 109                 default:
 110                         err ("%s:%s _HPP obj type incorrect\n", __FUNCTION__,
 111                                         path_name);
 112                         status = AE_ERROR;
 113                         goto free_and_return;
 114                 }
 115         }
 116
 117         hpp->cache_line_size = nui[0];
 118         hpp->latency_timer = nui[1];
 119         hpp->enable_serr = nui[2];
 120         hpp->enable_perr = nui[3];
 121
 122         dbg("  _HPP: cache_line_size=0x%x\n", hpp->cache_line_size);
 123         dbg("  _HPP: latency timer  =0x%x\n", hpp->latency_timer);
 124         dbg("  _HPP: enable SERR    =0x%x\n", hpp->enable_serr);
 125         dbg("  _HPP: enable PERR    =0x%x\n", hpp->enable_perr);
 126
 127 free_and_return:
 128         kfree(ret_buf.pointer);
 129         return status;
 130 }
 131
 132 static void acpi_run_oshp(acpi_handle handle)
 133 {
 134         acpi_status             status;
 135         u8                      *path_name = acpi_path_name(handle);
 136
 137         /* run OSHP */
 138         status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
 139         if (ACPI_FAILURE(status)) {
 140                 err("%s:%s OSHP fails=0x%x\n", __FUNCTION__, path_name,
 141                                 status);
 142         } else {
 143                 dbg("%s:%s OSHP passes\n", __FUNCTION__, path_name);
 144         }
 145 }
 146
 147 int shpchprm_get_physical_slot_number(struct controller *ctrl, u32 *sun, u8 busnum, u8 devnum)
 148 {
 149         int offset = devnum - ctrl->slot_device_offset;
 150
 151         dbg("%s: ctrl->slot_num_inc %d, offset %d\n", __FUNCTION__, ctrl->slot_num_inc, offset);
 152         *sun = (u8) (ctrl->first_slot + ctrl->slot_num_inc *offset);
 153         return 0;
 154 }
 155
 156 void get_hp_hw_control_from_firmware(struct pci_dev *dev)
 157 {
 158         /*
 159          * OSHP is an optional ACPI firmware control method. If present,
 160          * we need to run it to inform BIOS that we will control SHPC
 161          * hardware from now on.
 162          */
 163         acpi_handle handle = DEVICE_ACPI_HANDLE(&(dev->dev));
 164         if (!handle)
 165                 return;
 166         acpi_run_oshp(handle);
 167 }
 168
 169 void get_hp_params_from_firmware(struct pci_dev *dev,
 170                 struct hotplug_params *hpp)
 171 {
 172         acpi_status status = AE_NOT_FOUND;
 173         struct pci_dev *pdev = dev;
 174
 175         /*
 176          * _HPP settings apply to all child buses, until another _HPP is
 177          * encountered. If we don't find an _HPP for the input pci dev,
 178          * look for it in the parent device scope since that would apply to
 179          * this pci dev. If we don't find any _HPP, use hardcoded defaults
 180          */
 181         while (pdev && (ACPI_FAILURE(status))) {
 182                 acpi_handle handle = DEVICE_ACPI_HANDLE(&(pdev->dev));
 183                 if (!handle)
 184                         break;
 185                 status = acpi_run_hpp(handle, hpp);
 186                 if (!(pdev->bus->parent))
 187                         break;
 188                 /* Check if a parent object supports _HPP */
 189                 pdev = pdev->bus->parent->self;
 190         }
 191 }
 192