michaelh/zephyr
1
0
Fork 0
Code Releases Activity

drivers: serial: modify ns16550 to use extended FIFO

Browse source 
Cyclone V SoC FPGA supports 128Byte FIFO for UART communication,
this modification adds a feature to use 128byte FIFO serial UART

Signed-off-by: Esteban Valverde <esteban.valverde.vega@intel.com>
This commit is contained in:
Esteban Valverde 2022-04-26 10:59:56 +01:00 • committed by Anas Nashif
commit 797b6784bb
2 changed files with 16 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

12
drivers/serial/Kconfig.ns16550
View file

@ -28,12 +28,24 @@ config UART_NS16550_DRV_CMD
Says n if not sure. Says n if not sure.
choice
prompt "UART type"
default UART_NS16750
help
Select UART device type
config UART_NS16750 config UART_NS16750
bool "UART 16750 (64-bytes FIFO and auto flow control)" bool "UART 16750 (64-bytes FIFO and auto flow control)"
help help
This enables support for 64-bytes FIFO and automatic hardware This enables support for 64-bytes FIFO and automatic hardware
flow control if UART controller is 16750. flow control if UART controller is 16750.
config UART_NS16950
bool "UART 16950 (128-bytes FIFO and auto flow control)"
help
This enables support for 128-bytes FIFO and automatic hardware flow control.
endchoice
config UART_NS16550_ACCESS_WORD_ONLY config UART_NS16550_ACCESS_WORD_ONLY
bool "NS16550 only allows word access" bool "NS16550 only allows word access"
help help

5
drivers/serial/uart_ns16550.c
View file

@ -89,6 +89,7 @@ BUILD_ASSERT(IS_ENABLED(CONFIG_PCIE), "NS16550(s) in DT need CONFIG_PCIE");
#define IIR_MASK 0x07 /* interrupt id bits mask */ #define IIR_MASK 0x07 /* interrupt id bits mask */
#define IIR_ID 0x06 /* interrupt ID mask without NIP */ #define IIR_ID 0x06 /* interrupt ID mask without NIP */
#define IIR_FE 0xC0 /* FIFO mode enabled */ #define IIR_FE 0xC0 /* FIFO mode enabled */
#define IIR_CH 0x0C /* Character timeout*/
/* equates for FIFO control register */ /* equates for FIFO control register */
@ -447,7 +448,7 @@ static int uart_ns16550_configure(const struct device *dev,
uart_cfg.data_bits | uart_cfg.stop_bits | uart_cfg.parity); uart_cfg.data_bits | uart_cfg.stop_bits | uart_cfg.parity);
mdc = MCR_OUT2 | MCR_RTS | MCR_DTR; mdc = MCR_OUT2 | MCR_RTS | MCR_DTR;
#ifdef CONFIG_UART_NS16750 #if defined(CONFIG_UART_NS16750) || defined(CONFIG_UART_NS16950)
if (cfg->flow_ctrl == UART_CFG_FLOW_CTRL_RTS_CTS) { if (cfg->flow_ctrl == UART_CFG_FLOW_CTRL_RTS_CTS) {
mdc |= MCR_AFCE; mdc |= MCR_AFCE;
} }
@ -470,6 +471,8 @@ static int uart_ns16550_configure(const struct device *dev,
if ((INBYTE(IIR(dev)) & IIR_FE) == IIR_FE) { if ((INBYTE(IIR(dev)) & IIR_FE) == IIR_FE) {
#ifdef CONFIG_UART_NS16750 #ifdef CONFIG_UART_NS16750
dev_data->fifo_size = 64; dev_data->fifo_size = 64;
#elif defined(CONFIG_UART_NS16950)
dev_data->fifo_size = 128;
#else #else
dev_data->fifo_size = 16; dev_data->fifo_size = 16;
#endif #endif