acrn-hypervisor/hypervisor/debug/uart16550.c

279 lines
6.5 KiB
C

/*
* Copyright (C) 2018 Intel Corporation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <types.h>
#include <x86/lib/spinlock.h>
#include <pci.h>
#include <x86/pgtable.h>
#include <uart16550.h>
#include <x86/io.h>
#include <x86/mmu.h>
#define MAX_BDF_LEN 8
struct console_uart {
bool enabled;
enum serial_dev_type type;
uint16_t port_address;
void *mmio_base_vaddr;
union pci_bdf bdf;
spinlock_t rx_lock;
spinlock_t tx_lock;
uint32_t reg_width;
};
#if defined(CONFIG_SERIAL_PIO_BASE)
static struct console_uart uart = {
.enabled = true,
.type = PIO,
.port_address = CONFIG_SERIAL_PIO_BASE,
.reg_width = 1,
};
#elif defined(CONFIG_SERIAL_PCI_BDF)
static struct console_uart uart = {
.enabled = true,
.type = PCI,
.bdf.value = CONFIG_SERIAL_PCI_BDF,
.reg_width = 4,
};
#elif defined(CONFIG_SERIAL_MMIO_BASE)
static struct console_uart uart = {
.enabled = true,
.type = MMIO,
.mmio_base_vaddr = (void *)CONFIG_SERIAL_MMIO_BASE,
.reg_width = 1,
};
#endif
typedef uint32_t uart_reg_t;
/**
* @pre uart->enabled == true
*/
static inline uint32_t uart16550_read_reg(struct console_uart uart, uint16_t reg_idx)
{
if (uart.type == PIO) {
return pio_read8(uart.port_address + (reg_idx * uart.reg_width));
} else {
if (uart.reg_width == 4U) {
return mmio_read32(uart.mmio_base_vaddr + (reg_idx * uart.reg_width));
} else {
return mmio_read8(uart.mmio_base_vaddr + (reg_idx * uart.reg_width));
}
}
}
/**
* @pre uart->enabled == true
*/
static inline void uart16550_write_reg(struct console_uart uart, uint32_t val, uint16_t reg_idx)
{
if (uart.type == PIO) {
pio_write8(val, uart.port_address + (reg_idx * uart.reg_width));
} else {
if (uart.reg_width == 4U) {
mmio_write32(val, uart.mmio_base_vaddr + (reg_idx * uart.reg_width));
} else {
mmio_write8(val, uart.mmio_base_vaddr + (reg_idx * uart.reg_width));
}
}
}
static void uart16550_calc_baud_div(uint32_t ref_freq, uint32_t *baud_div_ptr, uint32_t baud_rate_arg)
{
uint32_t baud_rate = baud_rate_arg;
uint32_t baud_multiplier = baud_rate < BAUD_460800 ? 16U : 13U;
if (baud_rate == 0U) {
baud_rate = BAUD_115200;
}
*baud_div_ptr = ref_freq / (baud_multiplier * baud_rate);
}
/**
* @pre uart->enabled == true
*/
static void uart16550_set_baud_rate(uint32_t baud_rate)
{
uint32_t baud_div, duart_clock = UART_CLOCK_RATE;
uart_reg_t temp_reg;
/* Calculate baud divisor */
uart16550_calc_baud_div(duart_clock, &baud_div, baud_rate);
/* Enable DLL and DLM registers for setting the Divisor */
temp_reg = uart16550_read_reg(uart, UART16550_LCR);
temp_reg |= LCR_DLAB;
uart16550_write_reg(uart, temp_reg, UART16550_LCR);
/* Write the appropriate divisor value */
uart16550_write_reg(uart, ((baud_div >> 8U) & 0xFFU), UART16550_DLM);
uart16550_write_reg(uart, (baud_div & 0xFFU), UART16550_DLL);
/* Disable DLL and DLM registers */
temp_reg &= ~LCR_DLAB;
uart16550_write_reg(uart, temp_reg, UART16550_LCR);
}
void uart16550_init(bool early_boot)
{
void *mmio_base_va = NULL;
if (!uart.enabled) {
return;
}
if (!early_boot) {
if (uart.type == MMIO) {
mmio_base_va = hpa2hva(hva2hpa_early(uart.mmio_base_vaddr));
if (mmio_base_va != NULL) {
ppt_clear_user_bit((uint64_t)mmio_base_va, PDE_SIZE);
}
}
return;
}
/* if configure serial PCI BDF, get its base MMIO address */
if (uart.type == PCI) {
uint32_t bar0 = pci_pdev_read_cfg(uart.bdf, pci_bar_offset(0), 4U);
if ((bar0 & ~0xfU) == 0U) {
/* in case the PCI UART BAR is reset to 0 after boot */
uart.enabled = false;
return;
} else {
uint16_t cmd = (uint16_t)pci_pdev_read_cfg(uart.bdf, PCIR_COMMAND, 2U);
if ((bar0 & 0x3U) == PCIM_BAR_IO_SPACE) { /* IO Space */
uart.type = PIO;
uart.port_address = (uint16_t)(bar0 & PCI_BASE_ADDRESS_IO_MASK);
uart.reg_width = 1;
pci_pdev_write_cfg(uart.bdf, PCIR_COMMAND, 2U, cmd | PCIM_CMD_PORTEN);
} else {
if ((bar0 & 0xfU) == 0U) { /* 32 bits MMIO Space */
uart.type = MMIO;
uart.mmio_base_vaddr = hpa2hva_early((bar0 & PCI_BASE_ADDRESS_MEM_MASK));
pci_pdev_write_cfg(uart.bdf, PCIR_COMMAND, 2U, cmd | PCIM_CMD_MEMEN);
} else {
uart.enabled = false;
return;
}
}
}
}
spinlock_init(&uart.rx_lock);
spinlock_init(&uart.tx_lock);
/* Enable TX and RX FIFOs */
uart16550_write_reg(uart, FCR_FIFOE | FCR_RFR | FCR_TFR, UART16550_FCR);
/* Set-up data bits / parity / stop bits. */
uart16550_write_reg(uart, (LCR_WL8 | LCR_NB_STOP_BITS_1 | LCR_PARITY_NONE), UART16550_LCR);
/* Disable interrupts (we use polling) */
uart16550_write_reg(uart, UART_IER_DISABLE_ALL, UART16550_IER);
/* Set baud rate */
uart16550_set_baud_rate(BAUD_115200);
/* Data terminal ready + Request to send */
uart16550_write_reg(uart, MCR_RTS | MCR_DTR, UART16550_MCR);
}
char uart16550_getc(void)
{
char ret = -1;
uint64_t rflags;
if (!uart.enabled) {
return ret;
}
spinlock_irqsave_obtain(&uart.rx_lock, &rflags);
/* If a character has been received, read it */
if ((uart16550_read_reg(uart, UART16550_LSR) & LSR_DR) == LSR_DR) {
/* Read a character */
ret = uart16550_read_reg(uart, UART16550_RBR);
}
spinlock_irqrestore_release(&uart.rx_lock, rflags);
return ret;
}
/**
* @pre uart->enabled == true
*/
static void uart16550_putc(char c)
{
uint8_t temp;
uint32_t reg;
/* Ensure there are no further Transmit buffer write requests */
do {
reg = uart16550_read_reg(uart, UART16550_LSR);
} while ((reg & LSR_THRE) == 0U || (reg & LSR_TEMT) == 0U);
temp = (uint8_t)c;
/* Transmit the character. */
uart16550_write_reg(uart, (uint32_t)temp, UART16550_THR);
}
size_t uart16550_puts(const char *buf, uint32_t len)
{
uint32_t i;
uint64_t rflags;
if (!uart.enabled) {
return len;
}
spinlock_irqsave_obtain(&uart.tx_lock, &rflags);
for (i = 0U; i < len; i++) {
/* Transmit character */
uart16550_putc(*buf);
if (*buf == '\n') {
/* Append '\r', no need change the len */
uart16550_putc('\r');
}
buf++;
}
spinlock_irqrestore_release(&uart.tx_lock, rflags);
return len;
}
void uart16550_set_property(bool enabled, enum serial_dev_type uart_type, uint64_t data)
{
uart.enabled = enabled;
uart.type = uart_type;
uart.bdf.value = 0U;
if (uart_type == PIO) {
uart.port_address = data;
} else if (uart_type == PCI) {
uart.bdf.value = data;
uart.reg_width = 4;
} else if (uart_type == MMIO) {
uart.mmio_base_vaddr = (void *)data;
uart.reg_width = 1;
}
}
bool is_pci_dbg_uart(union pci_bdf bdf_value)
{
bool ret = false;
if (uart.enabled && (uart.bdf.value != 0)) {
if (bdf_value.value == uart.bdf.value) {
ret = true;
}
}
return ret;
}