projects / u-boot.git / blame
| Commit | Line | Data |
|---|---|---|
| a0609a8d BM |
1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* | |
| 3 | * Copyright (C) 2018, Bin Meng <[email protected]> | |
| 4 | */ | |
| 5 | ||
| f7ae49fc | 6 | #include <log.h> |
| 776cc201 | 7 | #include <acpi/acpi_table.h> |
| a0609a8d BM |
8 | #include <asm/io.h> |
| 9 | #include <asm/tables.h> | |
| 10 | ||
| 11 | static struct acpi_rsdp *acpi_valid_rsdp(struct acpi_rsdp *rsdp) | |
| 12 | { | |
| 13 | if (strncmp((char *)rsdp, RSDP_SIG, sizeof(RSDP_SIG) - 1) != 0) | |
| 14 | return NULL; | |
| 15 | ||
| 16 | debug("Looking on %p for valid checksum\n", rsdp); | |
| 17 | ||
| 18 | if (table_compute_checksum((void *)rsdp, 20) != 0) | |
| 19 | return NULL; | |
| 20 | debug("acpi rsdp checksum 1 passed\n"); | |
| 21 | ||
| 22 | if ((rsdp->revision > 1) && | |
| 23 | (table_compute_checksum((void *)rsdp, rsdp->length) != 0)) | |
| 24 | return NULL; | |
| 25 | debug("acpi rsdp checksum 2 passed\n"); | |
| 26 | ||
| 27 | return rsdp; | |
| 28 | } | |
| 29 | ||
| 30 | struct acpi_fadt *acpi_find_fadt(void) | |
| 31 | { | |
| 32 | char *p, *end; | |
| 33 | struct acpi_rsdp *rsdp = NULL; | |
| 34 | struct acpi_rsdt *rsdt; | |
| 35 | struct acpi_fadt *fadt = NULL; | |
| 36 | int i; | |
| 37 | ||
| 38 | /* Find RSDP */ | |
| 39 | for (p = (char *)ROM_TABLE_ADDR; p < (char *)ROM_TABLE_END; p += 16) { | |
| 40 | rsdp = acpi_valid_rsdp((struct acpi_rsdp *)p); | |
| 41 | if (rsdp) | |
| 42 | break; | |
| 43 | } | |
| 44 | ||
| 45 | if (!rsdp) | |
| 46 | return NULL; | |
| 47 | ||
| 48 | debug("RSDP found at %p\n", rsdp); | |
| 49 | rsdt = (struct acpi_rsdt *)(uintptr_t)rsdp->rsdt_address; | |
| 50 | ||
| 51 | end = (char *)rsdt + rsdt->header.length; | |
| 52 | debug("RSDT found at %p ends at %p\n", rsdt, end); | |
| 53 | ||
| 54 | for (i = 0; ((char *)&rsdt->entry[i]) < end; i++) { | |
| 55 | fadt = (struct acpi_fadt *)(uintptr_t)rsdt->entry[i]; | |
| 56 | if (strncmp((char *)fadt, "FACP", 4) == 0) | |
| 57 | break; | |
| 58 | fadt = NULL; | |
| 59 | } | |
| 60 | ||
| 61 | if (!fadt) | |
| 62 | return NULL; | |
| 63 | ||
| 64 | debug("FADT found at %p\n", fadt); | |
| 65 | return fadt; | |
| 66 | } | |
| 67 | ||
| 68 | void *acpi_find_wakeup_vector(struct acpi_fadt *fadt) | |
| 69 | { | |
| 70 | struct acpi_facs *facs; | |
| 71 | void *wake_vec; | |
| 72 | ||
| 73 | debug("Trying to find the wakeup vector...\n"); | |
| 74 | ||
| 75 | facs = (struct acpi_facs *)(uintptr_t)fadt->firmware_ctrl; | |
| 76 | ||
| 77 | if (!facs) { | |
| 78 | debug("No FACS found, wake up from S3 not possible.\n"); | |
| 79 | return NULL; | |
| 80 | } | |
| 81 | ||
| 82 | debug("FACS found at %p\n", facs); | |
| 83 | wake_vec = (void *)(uintptr_t)facs->firmware_waking_vector; | |
| 84 | debug("OS waking vector is %p\n", wake_vec); | |
| 85 | ||
| 86 | return wake_vec; | |
| 87 | } | |
| 88 | ||
| 89 | void enter_acpi_mode(int pm1_cnt) | |
| 90 | { | |
| 91 | u16 val = inw(pm1_cnt); | |
| 92 | ||
| 93 | /* | |
| 94 | * PM1_CNT register bit0 selects the power management event to be | |
| 95 | * either an SCI or SMI interrupt. When this bit is set, then power | |
| 96 | * management events will generate an SCI interrupt. When this bit | |
| 97 | * is reset power management events will generate an SMI interrupt. | |
| 98 | * | |
| 99 | * Per ACPI spec, it is the responsibility of the hardware to set | |
| 100 | * or reset this bit. OSPM always preserves this bit position. | |
| 101 | * | |
| 102 | * U-Boot does not support SMI. And we don't have plan to support | |
| 103 | * anything running in SMM within U-Boot. To create a legacy-free | |
| 104 | * system, and expose ourselves to OSPM as working under ACPI mode | |
| 105 | * already, turn this bit on. | |
| 106 | */ | |
| 107 | outw(val | PM1_CNT_SCI_EN, pm1_cnt); | |
| 108 | } |