projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 30919b0b | 2 | #include <linux/ioport.h> |
| 66441bd3 | 3 | #include <asm/e820/api.h> |
| 30919b0b | 4 | |
| 4dc2287c BH |
5 | static void resource_clip(struct resource *res, resource_size_t start, |
| 6 | resource_size_t end) | |
| 7 | { | |
| 8 | resource_size_t low = 0, high = 0; | |
| 9 | ||
| 10 | if (res->end < start || res->start > end) | |
| 11 | return; /* no conflict */ | |
| 12 | ||
| 13 | if (res->start < start) | |
| 14 | low = start - res->start; | |
| 15 | ||
| 16 | if (res->end > end) | |
| 17 | high = res->end - end; | |
| 18 | ||
| 19 | /* Keep the area above or below the conflict, whichever is larger */ | |
| 20 | if (low > high) | |
| 21 | res->end = start - 1; | |
| 22 | else | |
| 23 | res->start = end + 1; | |
| 24 | } | |
| 25 | ||
| 26 | static void remove_e820_regions(struct resource *avail) | |
| 27 | { | |
| 28 | int i; | |
| 8ec67d97 | 29 | struct e820_entry *entry; |
| 4dc2287c | 30 | |
| bf495573 IM |
31 | for (i = 0; i < e820_table->nr_entries; i++) { |
| 32 | entry = &e820_table->entries[i]; | |
| 4dc2287c BH |
33 | |
| 34 | resource_clip(avail, entry->addr, | |
| 35 | entry->addr + entry->size - 1); | |
| 36 | } | |
| 37 | } | |
| 38 | ||
| 30919b0b BH |
39 | void arch_remove_reservations(struct resource *avail) |
| 40 | { | |
| cbace46a CS |
41 | /* |
| 42 | * Trim out BIOS area (high 2MB) and E820 regions. We do not remove | |
| 43 | * the low 1MB unconditionally, as this area is needed for some ISA | |
| 44 | * cards requiring a memory range, e.g. the i82365 PCMCIA controller. | |
| 45 | */ | |
| 30919b0b | 46 | if (avail->flags & IORESOURCE_MEM) { |
| a2c606d5 | 47 | resource_clip(avail, BIOS_ROM_BASE, BIOS_ROM_END); |
| 4dc2287c BH |
48 | |
| 49 | remove_e820_regions(avail); | |
| 30919b0b BH |
50 | } |
| 51 | } |