uart: Add rounded clocking for 1 mbaud

This commit is contained in:
CTCaer 2020-04-30 03:34:05 +03:00
parent a00f25d2f9
commit 63768ccc99
5 changed files with 62 additions and 6 deletions

View file

@ -128,6 +128,29 @@ void clock_enable_uart(u32 idx)
clock_enable(&_clock_uart[idx]);
}
void clock_disable_uart(u32 idx)
{
clock_disable(&_clock_uart[idx]);
}
#define UART_SRC_CLK_DIV_EN (1 << 24)
int clock_uart_use_src_div(u32 idx, u32 baud)
{
u32 clk_src_div = CLOCK(_clock_uart[idx].source) & 0xE0000000;
if (baud == 1000000)
CLOCK(_clock_uart[idx].source) = clk_src_div | UART_SRC_CLK_DIV_EN | 49;
else
{
CLOCK(_clock_uart[idx].source) = clk_src_div | 2;
return 1;
}
return 0;
}
void clock_enable_i2c(u32 idx)
{
clock_enable(&_clock_i2c[idx]);

View file

@ -169,6 +169,8 @@ void clock_disable(const clock_t *clk);
/*! Clock control for specific hardware portions. */
void clock_enable_fuse(bool enable);
void clock_enable_uart(u32 idx);
void clock_disable_uart(u32 idx);
int clock_uart_use_src_div(u32 idx, u32 baud);
void clock_enable_i2c(u32 idx);
void clock_disable_i2c(u32 idx);
void clock_enable_se();

View file

@ -15,6 +15,7 @@
*/
#include "../soc/uart.h"
#include "../soc/clock.h"
#include "../soc/t210.h"
#include "../utils/util.h"
@ -28,12 +29,15 @@ void uart_init(u32 idx, u32 baud)
// Make sure no data is being sent.
uart_wait_idle(idx, UART_TX_IDLE);
// Set clock.
bool clk_type = clock_uart_use_src_div(idx, baud);
// Misc settings.
u32 rate = (8 * baud + 408000000) / (16 * baud);
u32 div = clk_type ? ((8 * baud + 408000000) / (16 * baud)) : 1; // DIV_ROUND_CLOSEST.
uart->UART_IER_DLAB = 0; // Disable interrupts.
uart->UART_LCR = UART_LCR_DLAB | UART_LCR_WORD_LENGTH_8; // Enable DLAB & set 8n1 mode.
uart->UART_THR_DLAB = (u8)rate; // Divisor latch LSB.
uart->UART_IER_DLAB = (u8)(rate >> 8); // Divisor latch MSB.
uart->UART_THR_DLAB = (u8)div; // Divisor latch LSB.
uart->UART_IER_DLAB = (u8)(div >> 8); // Divisor latch MSB.
uart->UART_LCR = UART_LCR_WORD_LENGTH_8; // Disable DLAB.
(void)uart->UART_SPR;

View file

@ -128,6 +128,29 @@ void clock_enable_uart(u32 idx)
clock_enable(&_clock_uart[idx]);
}
void clock_disable_uart(u32 idx)
{
clock_disable(&_clock_uart[idx]);
}
#define UART_SRC_CLK_DIV_EN (1 << 24)
int clock_uart_use_src_div(u32 idx, u32 baud)
{
u32 clk_src_div = CLOCK(_clock_uart[idx].source) & 0xE0000000;
if (baud == 1000000)
CLOCK(_clock_uart[idx].source) = clk_src_div | UART_SRC_CLK_DIV_EN | 49;
else
{
CLOCK(_clock_uart[idx].source) = clk_src_div | 2;
return 1;
}
return 0;
}
void clock_enable_i2c(u32 idx)
{
clock_enable(&_clock_i2c[idx]);

View file

@ -15,6 +15,7 @@
*/
#include "../soc/uart.h"
#include "../soc/clock.h"
#include "../soc/t210.h"
#include "../utils/util.h"
@ -28,12 +29,15 @@ void uart_init(u32 idx, u32 baud)
// Make sure no data is being sent.
uart_wait_idle(idx, UART_TX_IDLE);
// Set clock.
bool clk_type = clock_uart_use_src_div(idx, baud);
// Misc settings.
u32 rate = (8 * baud + 408000000) / (16 * baud);
u32 div = clk_type ? ((8 * baud + 408000000) / (16 * baud)) : 1; // DIV_ROUND_CLOSEST.
uart->UART_IER_DLAB = 0; // Disable interrupts.
uart->UART_LCR = UART_LCR_DLAB | UART_LCR_WORD_LENGTH_8; // Enable DLAB & set 8n1 mode.
uart->UART_THR_DLAB = (u8)rate; // Divisor latch LSB.
uart->UART_IER_DLAB = (u8)(rate >> 8); // Divisor latch MSB.
uart->UART_THR_DLAB = (u8)div; // Divisor latch LSB.
uart->UART_IER_DLAB = (u8)(div >> 8); // Divisor latch MSB.
uart->UART_LCR = UART_LCR_WORD_LENGTH_8; // Disable DLAB.
(void)uart->UART_SPR;