src/soc/intel/common/block/gpmr/gpmr.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <console/console.h>
   4 #include <intelblocks/gpmr.h>
   5 #include <intelblocks/ioc.h>
   6 #include <intelblocks/pcr.h>
   7 #include <soc/pcr_ids.h>
   8 #include <types.h>
   9
  10 /* GPMR Register read given offset */
  11 uint32_t gpmr_read32(uint16_t offset)
  12 {
  13         if (CONFIG(SOC_INTEL_COMMON_BLOCK_IOC))
  14                 return ioc_reg_read32(offset);
  15         else
  16                 return pcr_read32(PID_DMI, offset);
  17 }
  18
  19 /* GPMR Register write given offset and val */
  20 void gpmr_write32(uint16_t offset, uint32_t val)
  21 {
  22         if (CONFIG(SOC_INTEL_COMMON_BLOCK_IOC))
  23                 return ioc_reg_write32(offset, val);
  24         else
  25                 return pcr_write32(PID_DMI, offset, val);
  26 }
  27
  28 void gpmr_or32(uint16_t offset, uint32_t ordata)
  29 {
  30         if (CONFIG(SOC_INTEL_COMMON_BLOCK_IOC))
  31                 return ioc_reg_or32(offset, ordata);
  32         else
  33                 return pcr_or32(PID_DMI, offset, ordata);
  34 }
  35
  36 /* Check for available free gpmr */
  37 static int get_available_gpmr(void)
  38 {
  39         int i;
  40         uint32_t val;
  41
  42         for (i = 0; i < MAX_GPMR_REGS; i++) {
  43                 val = gpmr_read32(GPMR_DID_OFFSET(i));
  44                 if (!(val & GPMR_EN))
  45                         return i;
  46         }
  47         printk(BIOS_ERR, "%s: No available free gpmr found\n", __func__);
  48         return CB_ERR;
  49 }
  50
  51 /* Configure GPMR for the given base and size of extended BIOS Region */
  52 enum cb_err enable_gpmr(uint32_t base, uint32_t size, uint32_t dest_id)
  53 {
  54         int gpmr_num;
  55         uint32_t limit;
  56
  57         if (base & ~(GPMR_BASE_MASK << GPMR_BASE_SHIFT)) {
  58                 printk(BIOS_ERR, "base is not 64-KiB aligned!\n");
  59                 return CB_ERR;
  60         }
  61
  62         limit = base + (size - 1);
  63
  64         if (limit < base) {
  65                 printk(BIOS_ERR, "Invalid limit: limit cannot be less than base!\n");
  66                 return CB_ERR;
  67         }
  68
  69         if ((limit & ~GPMR_LIMIT_MASK) != 0xffff) {
  70                 printk(BIOS_ERR, "limit does not end on a 64-KiB boundary!\n");
  71                 return CB_ERR;
  72         }
  73
  74         /* Get available free GPMR */
  75         gpmr_num = get_available_gpmr();
  76         if (gpmr_num == CB_ERR)
  77                 return CB_ERR;
  78
  79         /* Program Range for the given decode window */
  80         gpmr_write32(GPMR_OFFSET(gpmr_num), (limit & GPMR_LIMIT_MASK) |
  81                 ((base >> GPMR_BASE_SHIFT) & GPMR_BASE_MASK));
  82
  83         /* Program source decode enable bit and the Destination ID */
  84         gpmr_write32(GPMR_DID_OFFSET(gpmr_num), dest_id | GPMR_EN);
  85
  86         return CB_SUCCESS;
  87 }