zephyr/drivers/serial/uart_xlnx_ps.c

1221 lines
36 KiB
C

/* uart_xlnx_ps.c - Xilinx Zynq family serial driver */
/*
* Copyright (c) 2018 Xilinx, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT xlnx_xuartps
/**
* @brief Xilnx Zynq Family Serial Driver
*
* This is the driver for the Xilinx Zynq family cadence serial device.
*
* Before individual UART port can be used, uart_xlnx_ps_init() has to be
* called to setup the port.
*
* - the following macro for the number of bytes between register addresses:
*
* UART_REG_ADDR_INTERVAL
*/
#include <errno.h>
#include <kernel.h>
#include <arch/cpu.h>
#include <zephyr/types.h>
#include <soc.h>
#include <init.h>
#include <toolchain.h>
#include <linker/sections.h>
#include <drivers/uart.h>
#include <sys/sys_io.h>
/* For all register offsets and bits / bit masks:
* Comp. Xilinx Zynq-7000 Technical Reference Manual (ug585), chap. B.33
*/
/* Register offsets within the UART device's register space */
#define XUARTPS_CR_OFFSET 0x0000U /**< Control Register [8:0] */
#define XUARTPS_MR_OFFSET 0x0004U /**< Mode Register [9:0] */
#define XUARTPS_IER_OFFSET 0x0008U /**< Interrupt Enable [12:0] */
#define XUARTPS_IDR_OFFSET 0x000CU /**< Interrupt Disable [12:0] */
#define XUARTPS_IMR_OFFSET 0x0010U /**< Interrupt Mask [12:0] */
#define XUARTPS_ISR_OFFSET 0x0014U /**< Interrupt Status [12:0]*/
#define XUARTPS_BAUDGEN_OFFSET 0x0018U /**< Baud Rate Generator [15:0] */
#define XUARTPS_RXTOUT_OFFSET 0x001CU /**< RX Timeout [7:0] */
#define XUARTPS_RXWM_OFFSET 0x0020U /**< RX FIFO Trigger Level [5:0] */
#define XUARTPS_MODEMCR_OFFSET 0x0024U /**< Modem Control [5:0] */
#define XUARTPS_MODEMSR_OFFSET 0x0028U /**< Modem Status [8:0] */
#define XUARTPS_SR_OFFSET 0x002CU /**< Channel Status [14:0] */
#define XUARTPS_FIFO_OFFSET 0x0030U /**< FIFO [7:0] */
#define XUARTPS_BAUDDIV_OFFSET 0x0034U /**< Baud Rate Divider [7:0] */
#define XUARTPS_FLOWDEL_OFFSET 0x0038U /**< Flow Delay [5:0] */
#define XUARTPS_TXWM_OFFSET 0x0044U /**< TX FIFO Trigger Level [5:0] */
#define XUARTPS_RXBS_OFFSET 0x0048U /**< RX FIFO Byte Status [11:0] */
/* Control Register Bits Definition */
#define XUARTPS_CR_STOPBRK 0x00000100U /**< Stop transmission of break */
#define XUARTPS_CR_STARTBRK 0x00000080U /**< Set break */
#define XUARTPS_CR_TORST 0x00000040U /**< RX timeout counter restart */
#define XUARTPS_CR_TX_DIS 0x00000020U /**< TX disabled. */
#define XUARTPS_CR_TX_EN 0x00000010U /**< TX enabled */
#define XUARTPS_CR_RX_DIS 0x00000008U /**< RX disabled. */
#define XUARTPS_CR_RX_EN 0x00000004U /**< RX enabled */
#define XUARTPS_CR_EN_DIS_MASK 0x0000003CU /**< Enable/disable Mask */
#define XUARTPS_CR_TXRST 0x00000002U /**< TX logic reset */
#define XUARTPS_CR_RXRST 0x00000001U /**< RX logic reset */
/* Mode Register Bits Definition */
#define XUARTPS_MR_CCLK 0x00000400U /**< Input clock select */
#define XUARTPS_MR_CHMODE_R_LOOP 0x00000300U /**< Remote loopback mode */
#define XUARTPS_MR_CHMODE_L_LOOP 0x00000200U /**< Local loopback mode */
#define XUARTPS_MR_CHMODE_ECHO 0x00000100U /**< Auto echo mode */
#define XUARTPS_MR_CHMODE_NORM 0x00000000U /**< Normal mode */
#define XUARTPS_MR_CHMODE_SHIFT 8U /**< Mode shift */
#define XUARTPS_MR_CHMODE_MASK 0x00000300U /**< Mode mask */
#define XUARTPS_MR_STOPMODE_2_BIT 0x00000080U /**< 2 stop bits */
#define XUARTPS_MR_STOPMODE_1_5_BIT 0x00000040U /**< 1.5 stop bits */
#define XUARTPS_MR_STOPMODE_1_BIT 0x00000000U /**< 1 stop bit */
#define XUARTPS_MR_STOPMODE_SHIFT 6U /**< Stop bits shift */
#define XUARTPS_MR_STOPMODE_MASK 0x000000A0U /**< Stop bits mask */
#define XUARTPS_MR_PARITY_NONE 0x00000020U /**< No parity mode */
#define XUARTPS_MR_PARITY_MARK 0x00000018U /**< Mark parity mode */
#define XUARTPS_MR_PARITY_SPACE 0x00000010U /**< Space parity mode */
#define XUARTPS_MR_PARITY_ODD 0x00000008U /**< Odd parity mode */
#define XUARTPS_MR_PARITY_EVEN 0x00000000U /**< Even parity mode */
#define XUARTPS_MR_PARITY_SHIFT 3U /**< Parity setting shift */
#define XUARTPS_MR_PARITY_MASK 0x00000038U /**< Parity mask */
#define XUARTPS_MR_CHARLEN_6_BIT 0x00000006U /**< 6 bits data */
#define XUARTPS_MR_CHARLEN_7_BIT 0x00000004U /**< 7 bits data */
#define XUARTPS_MR_CHARLEN_8_BIT 0x00000000U /**< 8 bits data */
#define XUARTPS_MR_CHARLEN_SHIFT 1U /**< Data Length shift */
#define XUARTPS_MR_CHARLEN_MASK 0x00000006U /**< Data length mask */
#define XUARTPS_MR_CLKSEL 0x00000001U /**< Input clock select */
/* Interrupt Register Bits Definition */
#define XUARTPS_IXR_RBRK 0x00002000U /**< Rx FIFO break detect interrupt */
#define XUARTPS_IXR_TOVR 0x00001000U /**< Tx FIFO Overflow interrupt */
#define XUARTPS_IXR_TNFUL 0x00000800U /**< Tx FIFO Nearly Full interrupt */
#define XUARTPS_IXR_TTRIG 0x00000400U /**< Tx Trig interrupt */
#define XUARTPS_IXR_DMS 0x00000200U /**< Modem status change interrupt */
#define XUARTPS_IXR_TOUT 0x00000100U /**< Timeout error interrupt */
#define XUARTPS_IXR_PARITY 0x00000080U /**< Parity error interrupt */
#define XUARTPS_IXR_FRAMING 0x00000040U /**< Framing error interrupt */
#define XUARTPS_IXR_RXOVR 0x00000020U /**< Overrun error interrupt */
#define XUARTPS_IXR_TXFULL 0x00000010U /**< TX FIFO full interrupt. */
#define XUARTPS_IXR_TXEMPTY 0x00000008U /**< TX FIFO empty interrupt. */
#define XUARTPS_IXR_RXFULL 0x00000004U /**< RX FIFO full interrupt. */
#define XUARTPS_IXR_RXEMPTY 0x00000002U /**< RX FIFO empty interrupt. */
#define XUARTPS_IXR_RTRIG 0x00000001U /**< RX FIFO trigger interrupt. */
#define XUARTPS_IXR_MASK 0x00003FFFU /**< Valid bit mask */
/* Modem Control Register Bits Definition */
#define XUARTPS_MODEMCR_FCM_RTS_CTS 0x00000020 /**< RTS/CTS hardware flow control. */
#define XUARTPS_MODEMCR_FCM_NONE 0x00000000 /**< No hardware flow control. */
#define XUARTPS_MODEMCR_FCM_MASK 0x00000020 /**< Hardware flow control mask. */
#define XUARTPS_MODEMCR_RTS_SHIFT 1U /**< RTS bit shift */
#define XUARTPS_MODEMCR_DTR_SHIFT 0U /**< DTR bit shift */
/* Channel Status Register */
#define XUARTPS_SR_TNFUL 0x00004000U /**< TX FIFO Nearly Full Status */
#define XUARTPS_SR_TTRIG 0x00002000U /**< TX FIFO Trigger Status */
#define XUARTPS_SR_FLOWDEL 0x00001000U /**< RX FIFO fill over flow delay */
#define XUARTPS_SR_TACTIVE 0x00000800U /**< TX active */
#define XUARTPS_SR_RACTIVE 0x00000400U /**< RX active */
#define XUARTPS_SR_TXFULL 0x00000010U /**< TX FIFO full */
#define XUARTPS_SR_TXEMPTY 0x00000008U /**< TX FIFO empty */
#define XUARTPS_SR_RXFULL 0x00000004U /**< RX FIFO full */
#define XUARTPS_SR_RXEMPTY 0x00000002U /**< RX FIFO empty */
#define XUARTPS_SR_RTRIG 0x00000001U /**< RX FIFO fill over trigger */
/** Device configuration structure */
struct uart_xlnx_ps_dev_config {
struct uart_device_config uconf;
uint32_t baud_rate;
};
/** Device data structure */
struct uart_xlnx_ps_dev_data_t {
uint32_t parity;
uint32_t stopbits;
uint32_t databits;
uint32_t flowctrl;
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
uart_irq_callback_user_data_t user_cb;
void *user_data;
#endif
};
#define DEV_CFG(dev) \
((const struct uart_xlnx_ps_dev_config * const) \
(dev)->config)
#define DEV_DATA(dev) \
((struct uart_xlnx_ps_dev_data_t *)(dev)->data)
static const struct uart_driver_api uart_xlnx_ps_driver_api;
/**
* @brief Disables the UART's RX and TX function.
*
* Writes 'Disable RX' and 'Disable TX' command bits into the respective
* UART's Command Register, thus disabling the operation of the UART.
*
* While writing the disable command bits, the opposing enable command
* bits, which are set when enabling the UART, are cleared.
*
* This function must be called before any configuration parameters
* of the UART are modified at run-time.
*
* @param reg_base Base address of the respective UART's register space.
*/
static void xlnx_ps_disable_uart(uint32_t reg_base)
{
uint32_t regval;
regval = sys_read32(reg_base + XUARTPS_CR_OFFSET);
regval &= (~XUARTPS_CR_EN_DIS_MASK);
/* Set control register bits [5]: TX_DIS and [3]: RX_DIS */
regval |= XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS;
sys_write32(regval, reg_base + XUARTPS_CR_OFFSET);
}
/**
* @brief Enables the UART's RX and TX function.
*
* Writes 'Enable RX' and 'Enable TX' command bits into the respective
* UART's Command Register, thus enabling the operation of the UART.
*
* While writing the enable command bits, the opposing disable command
* bits, which are set when disabling the UART, are cleared.
*
* This function must not be called while any configuration parameters
* of the UART are being modified at run-time.
*
* @param reg_base Base address of the respective UART's register space.
*/
static void xlnx_ps_enable_uart(uint32_t reg_base)
{
uint32_t regval;
regval = sys_read32(reg_base + XUARTPS_CR_OFFSET);
regval &= (~XUARTPS_CR_EN_DIS_MASK);
/* Set control register bits [4]: TX_EN and [2]: RX_EN */
regval |= XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN;
sys_write32(regval, reg_base + XUARTPS_CR_OFFSET);
}
/**
* @brief Calculates and sets the values of the BAUDDIV and BAUDGEN registers.
*
* Calculates and sets the values of the BAUDDIV and BAUDGEN registers, which
* determine the prescaler applied to the clock driving the UART, based on
* the target baud rate, which is provided as a decimal value.
*
* The calculation of the values to be written to the BAUDDIV and BAUDGEN
* registers is described in the Zynq-7000 TRM, chapter 19.2.3 'Baud Rate
* Generator'.
*
* @param dev UART device struct
* @param baud_rate The desired baud rate as a decimal value
*/
static void set_baudrate(const struct device *dev, uint32_t baud_rate)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t divisor, generator;
uint32_t baud;
uint32_t clk_freq;
uint32_t reg_base;
baud = dev_cfg->baud_rate;
clk_freq = dev_cfg->uconf.sys_clk_freq;
/* Calculate divisor and baud rate generator value */
if ((baud != 0) && (clk_freq != 0)) {
/* Covering case where input clock is so slow */
if (clk_freq < 1000000U && baud > 4800U) {
baud = 4800;
}
for (divisor = 4; divisor < 255; divisor++) {
uint32_t tmpbaud, bauderr;
generator = clk_freq / (baud * (divisor + 1));
if (generator < 2 || generator > 65535) {
continue;
}
tmpbaud = clk_freq / (generator * (divisor + 1));
if (baud > tmpbaud) {
bauderr = baud - tmpbaud;
} else {
bauderr = tmpbaud - baud;
}
if (((bauderr * 100) / baud) < 3) {
break;
}
}
/*
* Set baud rate divisor and generator.
* -> This function is always called from a context in which
* the receiver/transmitter is disabled, the baud rate can
* be changed safely at this time.
*/
reg_base = dev_cfg->uconf.regs;
sys_write32(divisor, reg_base + XUARTPS_BAUDDIV_OFFSET);
sys_write32(generator, reg_base + XUARTPS_BAUDGEN_OFFSET);
}
}
/**
* @brief Initialize individual UART port
*
* This routine is called to reset the chip in a quiescent state.
*
* @param dev UART device struct
*
* @return 0 if successful, failed otherwise
*/
static int uart_xlnx_ps_init(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_val;
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
/* Disable RX/TX before changing any configuration data */
xlnx_ps_disable_uart(reg_base);
/* Set initial character length / start/stop bit / parity configuration */
reg_val = sys_read32(reg_base + XUARTPS_MR_OFFSET);
reg_val &= (~(XUARTPS_MR_CHARLEN_MASK | XUARTPS_MR_STOPMODE_MASK |
XUARTPS_MR_PARITY_MASK));
reg_val |= XUARTPS_MR_CHARLEN_8_BIT | XUARTPS_MR_STOPMODE_1_BIT |
XUARTPS_MR_PARITY_NONE;
sys_write32(reg_val, reg_base + XUARTPS_MR_OFFSET);
/* Set RX FIFO trigger at 1 data bytes. */
sys_write32(0x01U, reg_base + XUARTPS_RXWM_OFFSET);
/* Set RX timeout to 1, which will be 4 character time */
sys_write32(0x1U, reg_base + XUARTPS_RXTOUT_OFFSET);
/* Disable all interrupts, polling mode is default */
sys_write32(XUARTPS_IXR_MASK, reg_base + XUARTPS_IDR_OFFSET);
/* Set the baud rate */
set_baudrate(dev, dev_cfg->baud_rate);
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
/* Clear any pending interrupt flags */
sys_write32(XUARTPS_IXR_MASK, reg_base + XUARTPS_ISR_OFFSET);
/* Attach to & unmask the corresponding interrupt vector */
dev_cfg->uconf.irq_config_func(dev);
#endif
xlnx_ps_enable_uart(reg_base);
return 0;
}
/**
* @brief Poll the device for input.
*
* @param dev UART device struct
* @param c Pointer to character
*
* @return 0 if a character arrived, -1 if the input buffer if empty.
*/
static int uart_xlnx_ps_poll_in(const struct device *dev, unsigned char *c)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_val;
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
if ((reg_val & XUARTPS_SR_RXEMPTY) == 0) {
*c = (unsigned char)sys_read32(reg_base +
XUARTPS_FIFO_OFFSET);
return 0;
} else {
return -1;
}
}
/**
* @brief Output a character in polled mode.
*
* Checks if the transmitter is empty. If empty, a character is written to
* the data register.
*
* If the hardware flow control is enabled then the handshake signal CTS has to
* be asserted in order to send a character.
*
* @param dev UART device struct
* @param c Character to send
*
* @return Sent character
*/
static void uart_xlnx_ps_poll_out(const struct device *dev, unsigned char c)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_val;
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
/* wait for transmitter to ready to accept a character */
do {
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
} while ((reg_val & XUARTPS_SR_TXEMPTY) == 0);
sys_write32((uint32_t)(c & 0xFF), reg_base + XUARTPS_FIFO_OFFSET);
do {
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
} while ((reg_val & XUARTPS_SR_TXEMPTY) == 0);
}
/**
* @brief Converts a parity enum value to a Mode Register bit mask.
*
* Converts a value of an enumeration type provided by the driver
* framework for the configuration of the UART's parity setting
* into a bit mask within the Mode Register.
*
* It is assumed that the Mode Register contents that are being
* modified within this function come with the bits modified by
* this function already masked out by the caller.
*
* @param mode_reg Pointer to the Mode Register contents to which
* the parity configuration shall be added.
* @param parity Enumeration value to be converted to a bit mask.
*
* @return Indication of success, always true for this function
* as all parity modes supported by the API are also supported
* by the hardware.
*/
static inline bool uart_xlnx_ps_cfg2ll_parity(
uint32_t *mode_reg,
enum uart_config_parity parity)
{
/*
* Translate the new parity configuration to the mode register's
* bits [5..3] (PAR):
* 000b : even
* 001b : odd
* 010b : space
* 011b : mark
* 1xxb : none
*/
switch (parity) {
default:
case UART_CFG_PARITY_EVEN:
*mode_reg |= XUARTPS_MR_PARITY_EVEN;
break;
case UART_CFG_PARITY_ODD:
*mode_reg |= XUARTPS_MR_PARITY_ODD;
break;
case UART_CFG_PARITY_SPACE:
*mode_reg |= XUARTPS_MR_PARITY_SPACE;
break;
case UART_CFG_PARITY_MARK:
*mode_reg |= XUARTPS_MR_PARITY_MARK;
break;
case UART_CFG_PARITY_NONE:
*mode_reg |= XUARTPS_MR_PARITY_NONE;
break;
}
return true;
}
/**
* @brief Converts a stop bit enum value to a Mode Register bit mask.
*
* Converts a value of an enumeration type provided by the driver
* framework for the configuration of the UART's stop bit setting
* into a bit mask within the Mode Register.
*
* It is assumed that the Mode Register contents that are being
* modified within this function come with the bits modified by
* this function already masked out by the caller.
*
* @param mode_reg Pointer to the Mode Register contents to which
* the stop bit configuration shall be added.
* @param stopbits Enumeration value to be converted to a bit mask.
*
* @return Indication of success or failure in case of an unsupported
* stop bit configuration being provided by the caller.
*/
static inline bool uart_xlnx_ps_cfg2ll_stopbits(
uint32_t *mode_reg,
enum uart_config_stop_bits stopbits)
{
/*
* Translate the new stop bit configuration to the mode register's
* bits [7..6] (NBSTOP):
* 00b : 1 stop bit
* 01b : 1.5 stop bits
* 10b : 2 stop bits
* 11b : reserved
*/
switch (stopbits) {
case UART_CFG_STOP_BITS_0_5:
/* Controller doesn't support 0.5 stop bits */
return false;
default:
case UART_CFG_STOP_BITS_1:
*mode_reg |= XUARTPS_MR_STOPMODE_1_BIT;
break;
case UART_CFG_STOP_BITS_1_5:
*mode_reg |= XUARTPS_MR_STOPMODE_1_5_BIT;
break;
case UART_CFG_STOP_BITS_2:
*mode_reg |= XUARTPS_MR_STOPMODE_2_BIT;
break;
}
return true;
}
/**
* @brief Converts a data bit enum value to a Mode Register bit mask.
*
* Converts a value of an enumeration type provided by the driver
* framework for the configuration of the UART's data bit setting
* into a bit mask within the Mode Register.
*
* It is assumed that the Mode Register contents that are being
* modified within this function come with the bits modified by
* this function already masked out by the caller.
*
* @param mode_reg Pointer to the Mode Register contents to which
* the data bit configuration shall be added.
* @param databits Enumeration value to be converted to a bit mask.
*
* @return Indication of success or failure in case of an unsupported
* data bit configuration being provided by the caller.
*/
static inline bool uart_xlnx_ps_cfg2ll_databits(
uint32_t *mode_reg,
enum uart_config_data_bits databits)
{
/*
* Translate the new data bit configuration to the mode register's
* bits [2..1] (CHRL):
* 0xb : 8 data bits
* 10b : 7 data bits
* 11b : 6 data bits
*/
switch (databits) {
case UART_CFG_DATA_BITS_5:
case UART_CFG_DATA_BITS_9:
/* Controller doesn't support 5 or 9 data bits */
return false;
default:
case UART_CFG_DATA_BITS_8:
*mode_reg |= XUARTPS_MR_CHARLEN_8_BIT;
break;
case UART_CFG_DATA_BITS_7:
*mode_reg |= XUARTPS_MR_CHARLEN_7_BIT;
break;
case UART_CFG_DATA_BITS_6:
*mode_reg |= XUARTPS_MR_CHARLEN_6_BIT;
break;
}
return true;
}
/**
* @brief Converts a flow control enum value to a Modem Control
* Register bit mask.
*
* Converts a value of an enumeration type provided by the driver
* framework for the configuration of the UART's flow control
* setting into a bit mask within the Modem Control Register.
*
* It is assumed that the Modem Control Register contents that are
* being modified within this function come with the bits modified
* by this function already masked out by the caller.
*
* @param modemcr_reg Pointer to the Modem Control Register contents
* to which the flow control configuration shall
* be added.
* @param hwctrl Enumeration value to be converted to a bit mask.
*
* @return Indication of success or failure in case of an unsupported
* flow control configuration being provided by the caller.
*/
static inline bool uart_xlnx_ps_cfg2ll_hwctrl(
uint32_t *modemcr_reg,
enum uart_config_flow_control hwctrl)
{
/*
* Translate the new flow control configuration to the modem
* control register's bit [5] (FCM):
* 0b : no flow control
* 1b : RTS/CTS
*/
if (hwctrl == UART_CFG_FLOW_CTRL_RTS_CTS) {
*modemcr_reg |= XUARTPS_MODEMCR_FCM_RTS_CTS;
} else if (hwctrl == UART_CFG_FLOW_CTRL_NONE) {
*modemcr_reg |= XUARTPS_MODEMCR_FCM_NONE;
} else {
/* Only no flow control or RTS/CTS is supported. */
return false;
}
return true;
}
/**
* @brief Configures the UART device at run-time.
*
* Configures the UART device at run-time according to the
* configuration data provided by the caller.
*
* @param dev UART device struct
* @param cfg The configuration parameters to be applied.
*
* @return 0 if the configuration completed successfully, ENOTSUP
* error if an unsupported configuration parameter is detected.
*/
static int uart_xlnx_ps_configure(const struct device *dev,
const struct uart_config *cfg)
{
struct uart_xlnx_ps_dev_config *dev_cfg =
(struct uart_xlnx_ps_dev_config *)DEV_CFG(dev);
uint32_t reg_base = dev_cfg->uconf.regs;
uint32_t mode_reg = 0;
uint32_t modemcr_reg = 0;
/* Read the current mode register & modem control register values */
mode_reg = sys_read32(reg_base + XUARTPS_MR_OFFSET);
modemcr_reg = sys_read32(reg_base + XUARTPS_MODEMCR_OFFSET);
/* Mask out all items that might be re-configured */
mode_reg &= (~XUARTPS_MR_PARITY_MASK);
mode_reg &= (~XUARTPS_MR_STOPMODE_MASK);
mode_reg &= (~XUARTPS_MR_CHARLEN_MASK);
modemcr_reg &= (~XUARTPS_MODEMCR_FCM_MASK);
/* Assemble the updated registers, validity checks contained within */
if ((!uart_xlnx_ps_cfg2ll_parity(&mode_reg, cfg->parity)) ||
(!uart_xlnx_ps_cfg2ll_stopbits(&mode_reg, cfg->stop_bits)) ||
(!uart_xlnx_ps_cfg2ll_databits(&mode_reg, cfg->data_bits)) ||
(!uart_xlnx_ps_cfg2ll_hwctrl(&modemcr_reg, cfg->flow_ctrl))) {
return -ENOTSUP;
}
/* Disable the controller before modifying any config registers */
xlnx_ps_disable_uart(reg_base);
/* Set the baud rate */
set_baudrate(dev, cfg->baudrate);
dev_cfg->baud_rate = cfg->baudrate;
/* Write the two control registers */
sys_write32(mode_reg, reg_base + XUARTPS_MR_OFFSET);
sys_write32(modemcr_reg, reg_base + XUARTPS_MODEMCR_OFFSET);
/* Re-enable the controller */
xlnx_ps_enable_uart(reg_base);
return 0;
};
/**
* @brief Converts a Mode Register bit mask to a parity configuration
* enum value.
*
* Converts a bit mask representing the UART's parity setting within
* the UART's Mode Register into a value of an enumeration type provided
* by the UART driver API.
*
* @param mode_reg The current Mode Register contents from which the
* parity setting shall be extracted.
*
* @return The current parity setting mapped to the UART driver API's
* enum type.
*/
static inline enum uart_config_parity uart_xlnx_ps_ll2cfg_parity(
uint32_t mode_reg)
{
/*
* Obtain the current parity configuration from the mode register's
* bits [5..3] (PAR):
* 000b : even -> reset value
* 001b : odd
* 010b : space
* 011b : mark
* 1xxb : none
*/
switch ((mode_reg & XUARTPS_MR_PARITY_MASK)) {
case XUARTPS_MR_PARITY_EVEN:
default:
return UART_CFG_PARITY_EVEN;
case XUARTPS_MR_PARITY_ODD:
return UART_CFG_PARITY_ODD;
case XUARTPS_MR_PARITY_SPACE:
return UART_CFG_PARITY_SPACE;
case XUARTPS_MR_PARITY_MARK:
return UART_CFG_PARITY_MARK;
case XUARTPS_MR_PARITY_NONE:
return UART_CFG_PARITY_NONE;
}
}
/**
* @brief Converts a Mode Register bit mask to a stop bit configuration
* enum value.
*
* Converts a bit mask representing the UART's stop bit setting within
* the UART's Mode Register into a value of an enumeration type provided
* by the UART driver API.
*
* @param mode_reg The current Mode Register contents from which the
* stop bit setting shall be extracted.
*
* @return The current stop bit setting mapped to the UART driver API's
* enum type.
*/
static inline enum uart_config_stop_bits uart_xlnx_ps_ll2cfg_stopbits(
uint32_t mode_reg)
{
/*
* Obtain the current stop bit configuration from the mode register's
* bits [7..6] (NBSTOP):
* 00b : 1 stop bit -> reset value
* 01b : 1.5 stop bits
* 10b : 2 stop bits
* 11b : reserved
*/
switch ((mode_reg & XUARTPS_MR_STOPMODE_MASK)) {
case XUARTPS_MR_STOPMODE_1_BIT:
default:
return UART_CFG_STOP_BITS_1;
case XUARTPS_MR_STOPMODE_1_5_BIT:
return UART_CFG_STOP_BITS_1_5;
case XUARTPS_MR_STOPMODE_2_BIT:
return UART_CFG_STOP_BITS_2;
}
}
/**
* @brief Converts a Mode Register bit mask to a data bit configuration
* enum value.
*
* Converts a bit mask representing the UART's data bit setting within
* the UART's Mode Register into a value of an enumeration type provided
* by the UART driver API.
*
* @param mode_reg The current Mode Register contents from which the
* data bit setting shall be extracted.
*
* @return The current data bit setting mapped to the UART driver API's
* enum type.
*/
static inline enum uart_config_data_bits uart_xlnx_ps_ll2cfg_databits(
uint32_t mode_reg)
{
/*
* Obtain the current data bit configuration from the mode register's
* bits [2..1] (CHRL):
* 0xb : 8 data bits -> reset value
* 10b : 7 data bits
* 11b : 6 data bits
*/
switch ((mode_reg & XUARTPS_MR_CHARLEN_MASK)) {
case XUARTPS_MR_CHARLEN_8_BIT:
default:
return UART_CFG_DATA_BITS_8;
case XUARTPS_MR_CHARLEN_7_BIT:
return UART_CFG_DATA_BITS_7;
case XUARTPS_MR_CHARLEN_6_BIT:
return UART_CFG_DATA_BITS_6;
}
}
/**
* @brief Converts a Modem Control Register bit mask to a flow control
* configuration enum value.
*
* Converts a bit mask representing the UART's flow control setting within
* the UART's Modem Control Register into a value of an enumeration type
* provided by the UART driver API.
*
* @param modemcr_reg The current Modem Control Register contents from
* which the parity setting shall be extracted.
*
* @return The current flow control setting mapped to the UART driver API's
* enum type.
*/
static inline enum uart_config_flow_control uart_xlnx_ps_ll2cfg_hwctrl(
uint32_t modemcr_reg)
{
/*
* Obtain the current flow control configuration from the modem
* control register's bit [5] (FCM):
* 0b : no flow control -> reset value
* 1b : RTS/CTS
*/
if ((modemcr_reg & XUARTPS_MODEMCR_FCM_MASK)
== XUARTPS_MODEMCR_FCM_RTS_CTS) {
return UART_CFG_FLOW_CTRL_RTS_CTS;
}
return UART_CFG_FLOW_CTRL_NONE;
}
/**
* @brief Returns the current configuration of the UART at run-time.
*
* Returns the current configuration of the UART at run-time by obtaining
* the current configuration from the UART's Mode and Modem Control Registers
* (exception: baud rate).
*
* @param dev UART device struct
* @param cfg Pointer to the data structure to which the current configuration
* shall be written.
*
* @return always 0.
*/
static int uart_xlnx_ps_config_get(const struct device *dev,
struct uart_config *cfg)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
/*
* Read the Mode & Modem control registers - they contain
* the current data / stop bit and parity settings (Mode
* Register) and the current flow control setting (Modem
* Control register).
*/
uint32_t reg_base = dev_cfg->uconf.regs;
uint32_t mode_reg = sys_read32(reg_base + XUARTPS_MR_OFFSET);
uint32_t modemcr_reg = sys_read32(reg_base + XUARTPS_MODEMCR_OFFSET);
cfg->baudrate = dev_cfg->baud_rate;
cfg->parity = uart_xlnx_ps_ll2cfg_parity(mode_reg);
cfg->stop_bits = uart_xlnx_ps_ll2cfg_stopbits(mode_reg);
cfg->data_bits = uart_xlnx_ps_ll2cfg_databits(mode_reg);
cfg->flow_ctrl = uart_xlnx_ps_ll2cfg_hwctrl(modemcr_reg);
return 0;
}
#if CONFIG_UART_INTERRUPT_DRIVEN
/**
* @brief Fill FIFO with data
*
* @param dev UART device struct
* @param tx_data Data to transmit
* @param size Number of bytes to send
*
* @return Number of bytes sent
*/
static int uart_xlnx_ps_fifo_fill(const struct device *dev,
const uint8_t *tx_data,
int size)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_val;
uint32_t reg_base;
int onum = 0;
reg_base = dev_cfg->uconf.regs;
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
while (onum < size && (reg_val & XUARTPS_SR_TXFULL) == 0) {
sys_write32((uint32_t)(tx_data[onum] & 0xFF),
reg_base + XUARTPS_FIFO_OFFSET);
onum++;
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
}
return onum;
}
/**
* @brief Read data from FIFO
*
* @param dev UART device struct
* @param rxData Data container
* @param size Container size
*
* @return Number of bytes read
*/
static int uart_xlnx_ps_fifo_read(const struct device *dev, uint8_t *rx_data,
const int size)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_val;
uint32_t reg_base;
int inum = 0;
reg_base = dev_cfg->uconf.regs;
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
while (inum < size && (reg_val & XUARTPS_SR_RXEMPTY) == 0) {
rx_data[inum] = (uint8_t)sys_read32(reg_base
+ XUARTPS_FIFO_OFFSET);
inum++;
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
}
return inum;
}
/**
* @brief Enable TX interrupt in IER
*
* @param dev UART device struct
*
* @return N/A
*/
static void uart_xlnx_ps_irq_tx_enable(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
sys_write32(
(XUARTPS_IXR_TTRIG | XUARTPS_IXR_TXEMPTY),
reg_base + XUARTPS_IER_OFFSET);
}
/**
* @brief Disable TX interrupt in IER
*
* @param dev UART device struct
*
* @return N/A
*/
static void uart_xlnx_ps_irq_tx_disable(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
sys_write32(
(XUARTPS_IXR_TTRIG | XUARTPS_IXR_TXEMPTY),
reg_base + XUARTPS_IDR_OFFSET);
}
/**
* @brief Check if Tx IRQ has been raised
*
* @param dev UART device struct
*
* @return 1 if an IRQ is ready, 0 otherwise
*/
static int uart_xlnx_ps_irq_tx_ready(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
uint32_t reg_val;
reg_base = dev_cfg->uconf.regs;
reg_val = sys_read32(reg_base + XUARTPS_ISR_OFFSET);
if ((reg_val & (XUARTPS_IXR_TTRIG | XUARTPS_IXR_TXEMPTY)) == 0) {
return 0;
} else {
sys_write32(
(XUARTPS_IXR_TTRIG | XUARTPS_IXR_TXEMPTY),
reg_base + XUARTPS_ISR_OFFSET);
return 1;
}
}
/**
* @brief Check if nothing remains to be transmitted
*
* @param dev UART device struct
*
* @return 1 if nothing remains to be transmitted, 0 otherwise
*/
static int uart_xlnx_ps_irq_tx_complete(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
uint32_t reg_val;
reg_base = dev_cfg->uconf.regs;
reg_val = sys_read32(reg_base + XUARTPS_SR_OFFSET);
if ((reg_val & XUARTPS_SR_TXEMPTY) == 0) {
return 0;
} else {
return 1;
}
}
/**
* @brief Enable RX interrupt in IER
*
* @param dev UART device struct
*
* @return N/A
*/
static void uart_xlnx_ps_irq_rx_enable(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
sys_write32(XUARTPS_IXR_RTRIG, reg_base + XUARTPS_IER_OFFSET);
}
/**
* @brief Disable RX interrupt in IER
*
* @param dev UART device struct
*
* @return N/A
*/
static void uart_xlnx_ps_irq_rx_disable(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
sys_write32(XUARTPS_IXR_RTRIG, reg_base + XUARTPS_IDR_OFFSET);
}
/**
* @brief Check if Rx IRQ has been raised
*
* @param dev UART device struct
*
* @return 1 if an IRQ is ready, 0 otherwise
*/
static int uart_xlnx_ps_irq_rx_ready(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
uint32_t reg_val;
reg_base = dev_cfg->uconf.regs;
reg_val = sys_read32(reg_base + XUARTPS_ISR_OFFSET);
if ((reg_val & XUARTPS_IXR_RTRIG) == 0) {
return 0;
} else {
sys_write32(XUARTPS_IXR_RTRIG, reg_base + XUARTPS_ISR_OFFSET);
return 1;
}
}
/**
* @brief Enable error interrupt in IER
*
* @param dev UART device struct
*
* @return N/A
*/
static void uart_xlnx_ps_irq_err_enable(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
sys_write32(
XUARTPS_IXR_TOVR /* [12] Transmitter FIFO Overflow */
| XUARTPS_IXR_TOUT /* [8] Receiver Timerout */
| XUARTPS_IXR_PARITY /* [7] Parity Error */
| XUARTPS_IXR_FRAMING /* [6] Receiver Framing Error */
| XUARTPS_IXR_RXOVR, /* [5] Receiver Overflow Error */
reg_base + XUARTPS_IER_OFFSET);
}
/**
* @brief Disable error interrupt in IER
*
* @param dev UART device struct
*
* @return 1 if an IRQ is ready, 0 otherwise
*/
static void uart_xlnx_ps_irq_err_disable(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
reg_base = dev_cfg->uconf.regs;
sys_write32(
XUARTPS_IXR_TOVR /* [12] Transmitter FIFO Overflow */
| XUARTPS_IXR_TOUT /* [8] Receiver Timerout */
| XUARTPS_IXR_PARITY /* [7] Parity Error */
| XUARTPS_IXR_FRAMING /* [6] Receiver Framing Error */
| XUARTPS_IXR_RXOVR, /* [5] Receiver Overflow Error */
reg_base + XUARTPS_IDR_OFFSET);
}
/**
* @brief Check if any IRQ is pending
*
* @param dev UART device struct
*
* @return 1 if an IRQ is pending, 0 otherwise
*/
static int uart_xlnx_ps_irq_is_pending(const struct device *dev)
{
const struct uart_xlnx_ps_dev_config *dev_cfg = DEV_CFG(dev);
uint32_t reg_base;
uint32_t reg_imr;
uint32_t reg_isr;
reg_base = dev_cfg->uconf.regs;
reg_imr = sys_read32(reg_base + XUARTPS_IMR_OFFSET);
reg_isr = sys_read32(reg_base + XUARTPS_ISR_OFFSET);
if ((reg_imr & reg_isr) != 0) {
return 1;
} else {
return 0;
}
}
/**
* @brief Update cached contents of IIR
*
* @param dev UART device struct
*
* @return Always 1
*/
static int uart_xlnx_ps_irq_update(const struct device *dev)
{
(void)dev;
return 1;
}
/**
* @brief Set the callback function pointer for IRQ.
*
* @param dev UART device struct
* @param cb Callback function pointer.
*
* @return N/A
*/
static void uart_xlnx_ps_irq_callback_set(const struct device *dev,
uart_irq_callback_user_data_t cb,
void *cb_data)
{
struct uart_xlnx_ps_dev_data_t *dev_data = DEV_DATA(dev);
dev_data->user_cb = cb;
dev_data->user_data = cb_data;
}
/**
* @brief Interrupt ce routine.
*
* This simply calls the callback function, if one exists.
*
* @param arg Argument to ISR.
*
* @return N/A
*/
static void uart_xlnx_ps_isr(const struct device *dev)
{
const struct uart_xlnx_ps_dev_data_t *data = DEV_DATA(dev);
if (data->user_cb) {
data->user_cb(dev, data->user_data);
}
}
#endif /* CONFIG_UART_INTERRUPT_DRIVEN */
static const struct uart_driver_api uart_xlnx_ps_driver_api = {
.poll_in = uart_xlnx_ps_poll_in,
.poll_out = uart_xlnx_ps_poll_out,
.configure = uart_xlnx_ps_configure,
.config_get = uart_xlnx_ps_config_get,
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
.fifo_fill = uart_xlnx_ps_fifo_fill,
.fifo_read = uart_xlnx_ps_fifo_read,
.irq_tx_enable = uart_xlnx_ps_irq_tx_enable,
.irq_tx_disable = uart_xlnx_ps_irq_tx_disable,
.irq_tx_ready = uart_xlnx_ps_irq_tx_ready,
.irq_tx_complete = uart_xlnx_ps_irq_tx_complete,
.irq_rx_enable = uart_xlnx_ps_irq_rx_enable,
.irq_rx_disable = uart_xlnx_ps_irq_rx_disable,
.irq_rx_ready = uart_xlnx_ps_irq_rx_ready,
.irq_err_enable = uart_xlnx_ps_irq_err_enable,
.irq_err_disable = uart_xlnx_ps_irq_err_disable,
.irq_is_pending = uart_xlnx_ps_irq_is_pending,
.irq_update = uart_xlnx_ps_irq_update,
.irq_callback_set = uart_xlnx_ps_irq_callback_set,
#endif
};
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
#define UART_XLNX_PS_IRQ_CONF_FUNC_SET(port) \
.irq_config_func = uart_xlnx_ps_irq_config_##port,
#define UART_XLNX_PS_IRQ_CONF_FUNC(port) \
static void uart_xlnx_ps_irq_config_##port(const struct device *dev) \
{ \
IRQ_CONNECT(DT_INST_IRQN(port), \
DT_INST_IRQ(port, priority), \
uart_xlnx_ps_isr, DEVICE_DT_INST_GET(port), \
0); \
irq_enable(DT_INST_IRQN(port)); \
}
#else
#define UART_XLNX_PS_IRQ_CONF_FUNC_SET(port)
#define UART_XLNX_PS_IRQ_CONF_FUNC(port)
#endif /*CONFIG_UART_INTERRUPT_DRIVEN */
#define UART_XLNX_PS_DEV_DATA(port) \
static struct uart_xlnx_ps_dev_data_t uart_xlnx_ps_dev_data_##port
#define UART_XLNX_PS_DEV_CFG(port) \
static struct uart_xlnx_ps_dev_config uart_xlnx_ps_dev_cfg_##port = { \
.uconf = { \
.regs = DT_INST_REG_ADDR(port), \
.sys_clk_freq = DT_INST_PROP(port, clock_frequency), \
UART_XLNX_PS_IRQ_CONF_FUNC_SET(port) \
}, \
.baud_rate = DT_INST_PROP(port, current_speed), \
}
#define UART_XLNX_PS_INIT(port) \
DEVICE_DT_INST_DEFINE(port, \
uart_xlnx_ps_init, \
device_pm_control_nop, \
&uart_xlnx_ps_dev_data_##port, \
&uart_xlnx_ps_dev_cfg_##port, \
PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
&uart_xlnx_ps_driver_api)
#define UART_XLNX_INSTANTIATE(inst) \
UART_XLNX_PS_IRQ_CONF_FUNC(inst); \
UART_XLNX_PS_DEV_DATA(inst); \
UART_XLNX_PS_DEV_CFG(inst); \
UART_XLNX_PS_INIT(inst);
DT_INST_FOREACH_STATUS_OKAY(UART_XLNX_INSTANTIATE)