1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2016 Stefan Roese <sr@denx.de> 4 */ 5 6 #include <common.h> 7 #include <asm/io.h> 8 #include <asm/pnp_def.h> 9 10 #define WINBOND_ENTRY_KEY 0x87 11 #define WINBOND_EXIT_KEY 0xaa 12 13 /* Enable configuration: pass entry key '0x87' into index port dev twice */ 14 static void pnp_enter_conf_state(u16 dev) 15 { 16 u16 port = dev >> 8; 17 18 outb(WINBOND_ENTRY_KEY, port); 19 outb(WINBOND_ENTRY_KEY, port); 20 } 21 22 /* Disable configuration: pass exit key '0xAA' into index port dev */ 23 static void pnp_exit_conf_state(u16 dev) 24 { 25 u16 port = dev >> 8; 26 27 outb(WINBOND_EXIT_KEY, port); 28 } 29 30 /* Bring up early serial debugging output before the RAM is initialized */ 31 void winbond_enable_serial(uint dev, uint iobase, uint irq) 32 { 33 pnp_enter_conf_state(dev); 34 pnp_set_logical_device(dev); 35 pnp_set_enable(dev, 0); 36 pnp_set_iobase(dev, PNP_IDX_IO0, iobase); 37 pnp_set_irq(dev, PNP_IDX_IRQ0, irq); 38 pnp_set_enable(dev, 1); 39 pnp_exit_conf_state(dev); 40 } 41