Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /* -*- linux-c -*- ------------------------------------------------------- *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *   Copyright (C) 1991, 1992 Linus Torvalds
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  *   Copyright 2007 rPath, Inc. - All Rights Reserved
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  *   Copyright 2009 Intel Corporation; author H. Peter Anvin
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  *   Original APM BIOS checking by Stephen Rothwell, May 1994
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  *   (sfr@canb.auug.org.au)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  * ----------------------------------------------------------------------- */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)  * Get APM BIOS information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include "boot.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) int query_apm_bios(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	struct biosregs ireg, oreg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	/* APM BIOS installation check */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 	initregs(&ireg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	ireg.ah = 0x53;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	intcall(0x15, &ireg, &oreg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	if (oreg.flags & X86_EFLAGS_CF)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 		return -1;		/* No APM BIOS */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	if (oreg.bx != 0x504d)		/* "PM" signature */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 		return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	if (!(oreg.cx & 0x02))		/* 32 bits supported? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 		return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	/* Disconnect first, just in case */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	ireg.al = 0x04;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	intcall(0x15, &ireg, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	/* 32-bit connect */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	ireg.al = 0x03;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	intcall(0x15, &ireg, &oreg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	boot_params.apm_bios_info.cseg        = oreg.ax;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	boot_params.apm_bios_info.offset      = oreg.ebx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	boot_params.apm_bios_info.cseg_16     = oreg.cx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	boot_params.apm_bios_info.dseg        = oreg.dx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	boot_params.apm_bios_info.cseg_len    = oreg.si;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 	boot_params.apm_bios_info.cseg_16_len = oreg.hsi;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	boot_params.apm_bios_info.dseg_len    = oreg.di;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	if (oreg.flags & X86_EFLAGS_CF)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 		return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	/* Redo the installation check as the 32-bit connect;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 	   some BIOSes return different flags this way... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	ireg.al = 0x00;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 	intcall(0x15, &ireg, &oreg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	if ((oreg.eflags & X86_EFLAGS_CF) || oreg.bx != 0x504d) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		/* Failure with 32-bit connect, try to disconnect and ignore */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 		ireg.al = 0x04;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 		intcall(0x15, &ireg, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 		return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	boot_params.apm_bios_info.version = oreg.ax;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	boot_params.apm_bios_info.flags   = oreg.cx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)