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/module.h>
  28 #include <linux/kernel.h>
  29 #include <linux/types.h>
  30 #include <linux/pci.h>
  31 #include <acpi/acpi.h>
  32 #include <acpi/acpi_bus.h>
  33 #include <acpi/actypes.h>
  34 #include "shpchp.h"
  35
  36 #define METHOD_NAME__SUN        "_SUN"
  37 #define METHOD_NAME__HPP        "_HPP"
  38 #define METHOD_NAME_OSHP        "OSHP"
  39
  40 static u8 * acpi_path_name( acpi_handle handle)
  41 {
  42         acpi_status             status;
  43         static u8       path_name[ACPI_PATHNAME_MAX];
  44         struct acpi_buffer              ret_buf = { ACPI_PATHNAME_MAX, path_name };
  45
  46         memset(path_name, 0, sizeof (path_name));
  47         status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &ret_buf);
  48
  49         if (ACPI_FAILURE(status))
  50                 return NULL;
  51         else
  52                 return path_name;
  53 }
  54
  55 static acpi_status
  56 acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
  57 {
  58         acpi_status             status;
  59         u8                      nui[4];
  60         struct acpi_buffer      ret_buf = { 0, NULL};
  61         union acpi_object       *ext_obj, *package;
  62         u8                      *path_name = acpi_path_name(handle);
  63         int                     i, len = 0;
  64
  65         /* get _hpp */
  66         status = acpi_evaluate_object(handle, METHOD_NAME__HPP, NULL, &ret_buf);
  67         switch (status) {
  68         case AE_BUFFER_OVERFLOW:
  69                 ret_buf.pointer = kmalloc (ret_buf.length, GFP_KERNEL);
  70                 if (!ret_buf.pointer) {
  71                         err ("%s:%s alloc for _HPP fail\n", __FUNCTION__,
  72                                         path_name);
  73                         return AE_NO_MEMORY;
  74                 }
  75                 status = acpi_evaluate_object(handle, METHOD_NAME__HPP,
  76                                 NULL, &ret_buf);
  77                 if (ACPI_SUCCESS(status))
  78                         break;
  79         default:
  80                 if (ACPI_FAILURE(status)) {
  81                         dbg("%s:%s _HPP fail=0x%x\n", __FUNCTION__,
  82                                         path_name, status);
  83                         return status;
  84                 }
  85         }
  86
  87         ext_obj = (union acpi_object *) ret_buf.pointer;
  88         if (ext_obj->type != ACPI_TYPE_PACKAGE) {
  89                 err ("%s:%s _HPP obj not a package\n", __FUNCTION__,
  90                                 path_name);
  91                 status = AE_ERROR;
  92                 goto free_and_return;
  93         }
  94
  95         len = ext_obj->package.count;
  96         package = (union acpi_object *) ret_buf.pointer;
  97         for ( i = 0; (i < len) || (i < 4); i++) {
  98                 ext_obj = (union acpi_object *) &package->package.elements[i];
  99                 switch (ext_obj->type) {
 100                 case ACPI_TYPE_INTEGER:
 101                         nui[i] = (u8)ext_obj->integer.value;
 102                         break;
 103                 default:
 104                         err ("%s:%s _HPP obj type incorrect\n", __FUNCTION__,
 105                                         path_name);
 106                         status = AE_ERROR;
 107                         goto free_and_return;
 108                 }
 109         }
 110
 111         hpp->cache_line_size = nui[0];
 112         hpp->latency_timer = nui[1];
 113         hpp->enable_serr = nui[2];
 114         hpp->enable_perr = nui[3];
 115
 116         dbg("  _HPP: cache_line_size=0x%x\n", hpp->cache_line_size);
 117         dbg("  _HPP: latency timer  =0x%x\n", hpp->latency_timer);
 118         dbg("  _HPP: enable SERR    =0x%x\n", hpp->enable_serr);
 119         dbg("  _HPP: enable PERR    =0x%x\n", hpp->enable_perr);
 120
 121 free_and_return:
 122         kfree(ret_buf.pointer);
 123         return status;
 124 }
 125
 126 static void acpi_run_oshp(acpi_handle handle)
 127 {
 128         acpi_status             status;
 129         u8                      *path_name = acpi_path_name(handle);
 130
 131         /* run OSHP */
 132         status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
 133         if (ACPI_FAILURE(status)) {
 134                 err("%s:%s OSHP fails=0x%x\n", __FUNCTION__, path_name,
 135                                 status);
 136         } else {
 137                 dbg("%s:%s OSHP passes\n", __FUNCTION__, path_name);
 138         }
 139 }
 140
 141 int shpchprm_get_physical_slot_number(struct controller *ctrl, u32 *sun, u8 busnum, u8 devnum)
 142 {
 143         int offset = devnum - ctrl->slot_device_offset;
 144
 145         dbg("%s: ctrl->slot_num_inc %d, offset %d\n", __FUNCTION__, ctrl->slot_num_inc, offset);
 146         *sun = (u8) (ctrl->first_slot + ctrl->slot_num_inc *offset);
 147         return 0;
 148 }
 149
 150 void get_hp_hw_control_from_firmware(struct pci_dev *dev)
 151 {
 152         /*
 153          * OSHP is an optional ACPI firmware control method. If present,
 154          * we need to run it to inform BIOS that we will control SHPC
 155          * hardware from now on.
 156          */
 157         acpi_handle handle = DEVICE_ACPI_HANDLE(&(dev->dev));
 158         if (!handle)
 159                 return;
 160         acpi_run_oshp(handle);
 161 }
 162
 163 void get_hp_params_from_firmware(struct pci_dev *dev,
 164                 struct hotplug_params *hpp)
 165 {
 166         acpi_status status = AE_NOT_FOUND;
 167         struct pci_dev *pdev = dev;
 168
 169         /*
 170          * _HPP settings apply to all child buses, until another _HPP is
 171          * encountered. If we don't find an _HPP for the input pci dev,
 172          * look for it in the parent device scope since that would apply to
 173          * this pci dev. If we don't find any _HPP, use hardcoded defaults
 174          */
 175         while (pdev && (ACPI_FAILURE(status))) {
 176                 acpi_handle handle = DEVICE_ACPI_HANDLE(&(pdev->dev));
 177                 if (!handle)
 178                         break;
 179                 status = acpi_run_hpp(handle, hpp);
 180                 if (!(pdev->bus->parent))
 181                         break;
 182                 /* Check if a parent object supports _HPP */
 183                 pdev = pdev->bus->parent->self;
 184         }
 185 }
 186