hw/pci-host/pam.c

   1 /*
   2  * QEMU Smram/pam logic implementation
   3  *
   4  * Copyright (c) 2006 Fabrice Bellard
   5  * Copyright (c) 2011 Isaku Yamahata <yamahata at valinux co jp>
   6  *                    VA Linux Systems Japan K.K.
   7  * Copyright (c) 2012 Jason Baron <jbaron@redhat.com>
   8  *
   9  * Split out from piix.c
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  24  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  26  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  27  * THE SOFTWARE.
  28  */
  29
  30 #include "qom/object.h"
  31 #include "sysemu/sysemu.h"
  32 #include "hw/pci-host/pam.h"
  33
  34 void smram_update(MemoryRegion *smram_region, uint8_t smram,
  35                   uint8_t smm_enabled)
  36 {
  37     bool smram_enabled;
  38
  39     smram_enabled = ((smm_enabled && (smram & SMRAM_G_SMRAME)) ||
  40                         (smram & SMRAM_D_OPEN));
  41     memory_region_set_enabled(smram_region, !smram_enabled);
  42 }
  43
  44 void smram_set_smm(uint8_t *host_smm_enabled, int smm, uint8_t smram,
  45                    MemoryRegion *smram_region)
  46 {
  47     uint8_t smm_enabled = (smm != 0);
  48     if (*host_smm_enabled != smm_enabled) {
  49         *host_smm_enabled = smm_enabled;
  50         smram_update(smram_region, smram, *host_smm_enabled);
  51     }
  52 }
  53
  54 void init_pam(DeviceState *dev, MemoryRegion *ram_memory,
  55               MemoryRegion *system_memory, MemoryRegion *pci_address_space,
  56               PAMMemoryRegion *mem, uint32_t start, uint32_t size)
  57 {
  58     int i;
  59
  60     /* RAM */
  61     memory_region_init_alias(&mem->alias[3], OBJECT(dev), "pam-ram", ram_memory,
  62                              start, size);
  63     /* ROM (XXX: not quite correct) */
  64     memory_region_init_alias(&mem->alias[1], OBJECT(dev), "pam-rom", ram_memory,
  65                              start, size);
  66     memory_region_set_readonly(&mem->alias[1], true);
  67
  68     /* XXX: should distinguish read/write cases */
  69     memory_region_init_alias(&mem->alias[0], OBJECT(dev), "pam-pci", pci_address_space,
  70                              start, size);
  71     memory_region_init_alias(&mem->alias[2], OBJECT(dev), "pam-pci", ram_memory,
  72                              start, size);
  73
  74     for (i = 0; i < 4; ++i) {
  75         memory_region_set_enabled(&mem->alias[i], false);
  76         memory_region_add_subregion_overlap(system_memory, start,
  77                                             &mem->alias[i], 1);
  78     }
  79     mem->current = 0;
  80 }
  81
  82 void pam_update(PAMMemoryRegion *pam, int idx, uint8_t val)
  83 {
  84     assert(0 <= idx && idx <= 12);
  85
  86     memory_region_set_enabled(&pam->alias[pam->current], false);
  87     pam->current = (val >> ((!(idx & 1)) * 4)) & PAM_ATTR_MASK;
  88     memory_region_set_enabled(&pam->alias[pam->current], true);
  89 }