LXR uboot/arch/x86/cpu/braswell/early

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com>
   4 */
   5
   6#include <common.h>
   7#include <asm/io.h>
   8
   9#define PCI_DEV_CONFIG(segbus, dev, fn) ( \
  10                (((segbus) & 0xfff) << 20) | \
  11                (((dev) & 0x1f) << 15) | \
  12                (((fn)  & 0x07) << 12))
  13
  14/* Platform Controller Unit */
  15#define LPC_DEV                 0x1f
  16#define LPC_FUNC                0
  17
  18/* Enable UART */
  19#define UART_CONT               0x80
  20
  21/* UART PAD definitions */
  22#define UART_RXD_COMMUITY       1
  23#define UART_TXD_COMMUITY       1
  24#define UART_RXD_FAMILY         4
  25#define UART_TXD_FAMILY         4
  26#define UART_RXD_PAD            2
  27#define UART_TXD_PAD            7
  28#define UART_RXD_FUNC           3
  29#define UART_TXD_FUNC           3
  30
  31/* IO Memory */
  32#define IO_BASE_ADDRESS         0xfed80000
  33
  34static inline uint32_t gpio_pconf0(int community, int family, int pad)
  35{
  36        return IO_BASE_ADDRESS + community * 0x8000 + 0x4400 +
  37                family * 0x400 + pad * 8;
  38}
  39
  40static void gpio_select_func(int community, int family, int pad, int func)
  41{
  42        uint32_t pconf0_addr = gpio_pconf0(community, family, pad);
  43
  44        clrsetbits_le32(pconf0_addr, 0xf << 16, func << 16);
  45}
  46
  47static void x86_pci_write_config32(int dev, unsigned int where, u32 value)
  48{
  49        unsigned long addr;
  50
  51        addr = CONFIG_PCIE_ECAM_BASE | dev | (where & ~3);
  52        writel(value, addr);
  53}
  54
  55/* This can be called after memory-mapped PCI is working */
  56int setup_internal_uart(int enable)
  57{
  58        /* Enable or disable the legacy UART hardware */
  59        x86_pci_write_config32(PCI_DEV_CONFIG(0, LPC_DEV, LPC_FUNC), UART_CONT,
  60                               enable);
  61
  62        /* All done for the disable part, so just return */
  63        if (!enable)
  64                return 0;
  65
  66        /*
  67         * Set up the pads to the UART function. This allows the signals to
  68         * leave the chip
  69         */
  70        gpio_select_func(UART_RXD_COMMUITY, UART_RXD_FAMILY,
  71                         UART_RXD_PAD, UART_RXD_FUNC);
  72        gpio_select_func(UART_TXD_COMMUITY, UART_TXD_FAMILY,
  73                         UART_TXD_PAD, UART_TXD_FUNC);
  74
  75        return 0;
  76}
  77
  78void board_debug_uart_init(void)
  79{
  80        setup_internal_uart(1);
  81}
  82