x86: acpi: Move APIs unrelated to ACPI tables generation to a separate library
acpi_find_fadt(), acpi_find_wakeup_vector() and enter_acpi_mode()
are something unrelated to ACPI tables generation. Move these to
a separate library.
This also fixes several style issues reported by checkpatch in the
original codes.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
diff --git a/arch/x86/lib/acpi.c b/arch/x86/lib/acpi.c
new file mode 100644
index 0000000..cba9c24
--- /dev/null
+++ b/arch/x86/lib/acpi.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
+ */
+
+#include <common.h>
+#include <asm/acpi_table.h>
+#include <asm/io.h>
+#include <asm/tables.h>
+
+static struct acpi_rsdp *acpi_valid_rsdp(struct acpi_rsdp *rsdp)
+{
+ if (strncmp((char *)rsdp, RSDP_SIG, sizeof(RSDP_SIG) - 1) != 0)
+ return NULL;
+
+ debug("Looking on %p for valid checksum\n", rsdp);
+
+ if (table_compute_checksum((void *)rsdp, 20) != 0)
+ return NULL;
+ debug("acpi rsdp checksum 1 passed\n");
+
+ if ((rsdp->revision > 1) &&
+ (table_compute_checksum((void *)rsdp, rsdp->length) != 0))
+ return NULL;
+ debug("acpi rsdp checksum 2 passed\n");
+
+ return rsdp;
+}
+
+struct acpi_fadt *acpi_find_fadt(void)
+{
+ char *p, *end;
+ struct acpi_rsdp *rsdp = NULL;
+ struct acpi_rsdt *rsdt;
+ struct acpi_fadt *fadt = NULL;
+ int i;
+
+ /* Find RSDP */
+ for (p = (char *)ROM_TABLE_ADDR; p < (char *)ROM_TABLE_END; p += 16) {
+ rsdp = acpi_valid_rsdp((struct acpi_rsdp *)p);
+ if (rsdp)
+ break;
+ }
+
+ if (!rsdp)
+ return NULL;
+
+ debug("RSDP found at %p\n", rsdp);
+ rsdt = (struct acpi_rsdt *)(uintptr_t)rsdp->rsdt_address;
+
+ end = (char *)rsdt + rsdt->header.length;
+ debug("RSDT found at %p ends at %p\n", rsdt, end);
+
+ for (i = 0; ((char *)&rsdt->entry[i]) < end; i++) {
+ fadt = (struct acpi_fadt *)(uintptr_t)rsdt->entry[i];
+ if (strncmp((char *)fadt, "FACP", 4) == 0)
+ break;
+ fadt = NULL;
+ }
+
+ if (!fadt)
+ return NULL;
+
+ debug("FADT found at %p\n", fadt);
+ return fadt;
+}
+
+void *acpi_find_wakeup_vector(struct acpi_fadt *fadt)
+{
+ struct acpi_facs *facs;
+ void *wake_vec;
+
+ debug("Trying to find the wakeup vector...\n");
+
+ facs = (struct acpi_facs *)(uintptr_t)fadt->firmware_ctrl;
+
+ if (!facs) {
+ debug("No FACS found, wake up from S3 not possible.\n");
+ return NULL;
+ }
+
+ debug("FACS found at %p\n", facs);
+ wake_vec = (void *)(uintptr_t)facs->firmware_waking_vector;
+ debug("OS waking vector is %p\n", wake_vec);
+
+ return wake_vec;
+}
+
+void enter_acpi_mode(int pm1_cnt)
+{
+ u16 val = inw(pm1_cnt);
+
+ /*
+ * PM1_CNT register bit0 selects the power management event to be
+ * either an SCI or SMI interrupt. When this bit is set, then power
+ * management events will generate an SCI interrupt. When this bit
+ * is reset power management events will generate an SMI interrupt.
+ *
+ * Per ACPI spec, it is the responsibility of the hardware to set
+ * or reset this bit. OSPM always preserves this bit position.
+ *
+ * U-Boot does not support SMI. And we don't have plan to support
+ * anything running in SMM within U-Boot. To create a legacy-free
+ * system, and expose ourselves to OSPM as working under ACPI mode
+ * already, turn this bit on.
+ */
+ outw(val | PM1_CNT_SCI_EN, pm1_cnt);
+}