u-boot/include/serial.h

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#ifndef __SERIAL_H__
#define __SERIAL_H__
#include <post.h>
struct serial_device {
/* enough bytes to match alignment of following func pointer */
char name[16];
int (*start)(void);
int (*stop)(void);
void (*setbrg)(void);
int (*getc)(void);
int (*tstc)(void);
void (*putc)(const char c);
void (*puts)(const char *s);
#if CFG_POST & CONFIG_SYS_POST_UART
void (*loop)(int);
#endif
struct serial_device *next;
};
void default_serial_puts(const char *s);
extern struct serial_device serial_smc_device;
serial: Add semihosting driver This adds a serial driver which uses semihosting calls to read and write to the host's console. For convenience, if CONFIG_DM_SERIAL is enabled, we will instantiate a serial driver. This allows users to enable this driver (which has no physical device) without modifying their device trees or board files. We also implement a non-DM driver for SPL, or for much faster output in U-Boot proper. There are three ways to print to the console: Method Baud ================== ===== smh_putc in a loop 170 smh_puts 1600 smh_write with :tt 20000 ================== ===== These speeds were measured using a 175 character message with a J-Link adapter. For reference, U-Boot typically prints around 2700 characters during boot on this board. There are two major factors affecting the speed of these functions. First, each breakpoint incurs a delay. Second, each debugger memory transaction incurs a delay. smh_putc has a breakpoint and memory transaction for every character. smh_puts has one breakpoint, but still has to use a transaction for every character. This is because we don't know the length up front, so OpenOCD has to check if each character is nul. smh_write has only one breakpoint and one memory transfer. DM serial drivers can only implement a putc interface, so we are stuck with the slowest API. Non-DM drivers can implement puts, which is vastly more efficient. When the driver starts up, we try to open :tt. Since this is an extension, this may fail. If it does, we fall back to smh_puts. We don't check :semihosting-features, since there are nonconforming implementations (OpenOCD) which don't implement it (but *do* implement :tt). Some semihosting implementations (QEMU) don't handle READC properly. To work around this, we try to use open/read (much like for stdin) if possible. There is no non-blocking I/O available, so we don't implement pending. This will cause __serial_tstc to always return true. If CONFIG_SERIAL_RX_BUFFER is enabled, _serial_tstc will try and read characters forever. To avoid this, we depend on this config being disabled. Signed-off-by: Sean Anderson <sean.anderson@seco.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2022-03-22 20:59:24 +00:00
extern struct serial_device serial_smh_device;
extern struct serial_device serial_scc_device;
extern struct serial_device *default_serial_console(void);
#if defined(CONFIG_MPC83xx) || defined(CONFIG_MPC85xx) || \
defined(CONFIG_MPC86xx) || \
defined(CONFIG_ARCH_TEGRA) || defined(CONFIG_SYS_COREBOOT) || \
defined(CONFIG_MICROBLAZE)
extern struct serial_device serial0_device;
extern struct serial_device serial1_device;
#endif
extern struct serial_device eserial1_device;
extern struct serial_device eserial2_device;
extern struct serial_device eserial3_device;
extern struct serial_device eserial4_device;
extern struct serial_device eserial5_device;
extern struct serial_device eserial6_device;
extern void serial_register(struct serial_device *);
extern void serial_stdio_init(void);
extern int serial_assign(const char *name);
extern void serial_reinit_all(void);
int serial_initialize(void);
/* For usbtty */
#ifdef CONFIG_USB_TTY
struct stdio_dev;
int usbtty_getc(struct stdio_dev *dev);
void usbtty_putc(struct stdio_dev *dev, const char c);
void usbtty_puts(struct stdio_dev *dev, const char *str);
int usbtty_tstc(struct stdio_dev *dev);
#else
/* stubs */
#define usbtty_getc(dev) 0
#define usbtty_putc(dev, a)
#define usbtty_puts(dev, a)
#define usbtty_tstc(dev) 0
#endif /* CONFIG_USB_TTY */
struct udevice;
enum serial_par {
SERIAL_PAR_NONE,
SERIAL_PAR_ODD,
SERIAL_PAR_EVEN
};
#define SERIAL_PAR_SHIFT 0
#define SERIAL_PAR_MASK (0x03 << SERIAL_PAR_SHIFT)
#define SERIAL_SET_PARITY(parity) \
((parity << SERIAL_PAR_SHIFT) & SERIAL_PAR_MASK)
#define SERIAL_GET_PARITY(config) \
((config & SERIAL_PAR_MASK) >> SERIAL_PAR_SHIFT)
enum serial_bits {
SERIAL_5_BITS,
SERIAL_6_BITS,
SERIAL_7_BITS,
SERIAL_8_BITS
};
#define SERIAL_BITS_SHIFT 2
#define SERIAL_BITS_MASK (0x3 << SERIAL_BITS_SHIFT)
#define SERIAL_SET_BITS(bits) \
((bits << SERIAL_BITS_SHIFT) & SERIAL_BITS_MASK)
#define SERIAL_GET_BITS(config) \
((config & SERIAL_BITS_MASK) >> SERIAL_BITS_SHIFT)
enum serial_stop {
SERIAL_HALF_STOP, /* 0.5 stop bit */
SERIAL_ONE_STOP, /* 1 stop bit */
SERIAL_ONE_HALF_STOP, /* 1.5 stop bit */
SERIAL_TWO_STOP /* 2 stop bit */
};
#define SERIAL_STOP_SHIFT 4
#define SERIAL_STOP_MASK (0x3 << SERIAL_STOP_SHIFT)
#define SERIAL_SET_STOP(stop) \
((stop << SERIAL_STOP_SHIFT) & SERIAL_STOP_MASK)
#define SERIAL_GET_STOP(config) \
((config & SERIAL_STOP_MASK) >> SERIAL_STOP_SHIFT)
#define SERIAL_CONFIG(par, bits, stop) \
(par << SERIAL_PAR_SHIFT | \
bits << SERIAL_BITS_SHIFT | \
stop << SERIAL_STOP_SHIFT)
#define SERIAL_DEFAULT_CONFIG \
(SERIAL_PAR_NONE << SERIAL_PAR_SHIFT | \
SERIAL_8_BITS << SERIAL_BITS_SHIFT | \
SERIAL_ONE_STOP << SERIAL_STOP_SHIFT)
enum serial_chip_type {
SERIAL_CHIP_UNKNOWN = -1,
SERIAL_CHIP_16550_COMPATIBLE,
};
enum adr_space_type {
SERIAL_ADDRESS_SPACE_MEMORY = 0,
SERIAL_ADDRESS_SPACE_IO,
};
/**
* struct serial_device_info - structure to hold serial device info
*
* @type: type of the UART chip
* @addr_space: address space to access the registers
* @addr: physical address of the registers
* @reg_width: size (in bytes) of the IO accesses to the registers
* @reg_offset: offset to apply to the @addr from the start of the registers
* @reg_shift: quantity to shift the register offsets by
* @clock: UART base clock speed in Hz
* @baudrate: baud rate
*/
struct serial_device_info {
enum serial_chip_type type;
enum adr_space_type addr_space;
ulong addr;
u8 reg_width;
u8 reg_offset;
u8 reg_shift;
unsigned int clock;
unsigned int baudrate;
};
#define SERIAL_DEFAULT_ADDRESS 0xBADACCE5
#define SERIAL_DEFAULT_CLOCK (16 * 115200)
/**
* struct struct dm_serial_ops - Driver model serial operations
*
* The uclass interface is implemented by all serial devices which use
* driver model.
*/
struct dm_serial_ops {
/**
* setbrg() - Set up the baud rate generator
*
* Adjust baud rate divisors to set up a new baud rate for this
* device. Not all devices will support all rates. If the rate
* cannot be supported, the driver is free to select the nearest
* available rate. or return -EINVAL if this is not possible.
*
* @dev: Device pointer
* @baudrate: New baud rate to use
* @return 0 if OK, -ve on error
*/
int (*setbrg)(struct udevice *dev, int baudrate);
/**
* getc() - Read a character and return it
*
* If no character is available, this should return -EAGAIN without
* waiting.
*
* @dev: Device pointer
* @return character (0..255), -ve on error
*/
int (*getc)(struct udevice *dev);
/**
* putc() - Write a character
*
* @dev: Device pointer
* @ch: character to write
* @return 0 if OK, -ve on error
*/
int (*putc)(struct udevice *dev, const char ch);
/**
* puts() - Write a string
*
* This writes a string. This function should be implemented only if
* writing multiple characters at once is more performant than just
* calling putc() in a loop.
*
* If the whole string cannot be written at once, then this function
* should return the number of characters written. Returning a negative
* error code implies that no characters were written. If this function
* returns 0, then it will be called again with the same arguments.
*
* @dev: Device pointer
* @s: The string to write
* @len: The length of the string to write.
* @return The number of characters written on success, or -ve on error
*/
ssize_t (*puts)(struct udevice *dev, const char *s, size_t len);
/**
* pending() - Check if input/output characters are waiting
*
* This can be used to return an indication of the number of waiting
* characters if the driver knows this (e.g. by looking at the FIFO
* level). It is acceptable to return 1 if an indeterminant number
* of characters is waiting.
*
* This method is optional.
*
* @dev: Device pointer
* @input: true to check input characters, false for output
* @return number of waiting characters, 0 for none, -ve on error
*/
int (*pending)(struct udevice *dev, bool input);
/**
* clear() - Clear the serial FIFOs/holding registers
*
* This method is optional.
*
* This quickly clears any input/output characters from the UART.
* If this is not possible, but characters still exist, then it
* is acceptable to return -EAGAIN (try again) or -EINVAL (not
* supported).
*
* @dev: Device pointer
* @return 0 if OK, -ve on error
*/
int (*clear)(struct udevice *dev);
#if CFG_POST & CONFIG_SYS_POST_UART
/**
* loop() - Control serial device loopback mode
*
* @dev: Device pointer
* @on: 1 to turn loopback on, 0 to turn if off
*/
int (*loop)(struct udevice *dev, int on);
#endif
/**
* getconfig() - Get the uart configuration
* (parity, 5/6/7/8 bits word length, stop bits)
*
* Get a current config for this device.
*
* @dev: Device pointer
* @serial_config: Returns config information (see SERIAL_... above)
* @return 0 if OK, -ve on error
*/
int (*getconfig)(struct udevice *dev, uint *serial_config);
/**
* setconfig() - Set up the uart configuration
* (parity, 5/6/7/8 bits word length, stop bits)
*
* Set up a new config for this device.
*
* @dev: Device pointer
* @serial_config: number of bits, parity and number of stopbits to use
* @return 0 if OK, -ve on error
*/
int (*setconfig)(struct udevice *dev, uint serial_config);
/**
* getinfo() - Get serial device information
*
* @dev: Device pointer
* @info: struct serial_device_info to fill
* @return 0 if OK, -ve on error
*/
int (*getinfo)(struct udevice *dev, struct serial_device_info *info);
};
/**
* struct serial_dev_priv - information about a device used by the uclass
*
* @sdev: stdio device attached to this uart
*
* @buf: Pointer to the RX buffer
* @rd_ptr: Read pointer in the RX buffer
* @wr_ptr: Write pointer in the RX buffer
*/
struct serial_dev_priv {
struct stdio_dev *sdev;
char *buf;
int rd_ptr;
int wr_ptr;
};
/* Access the serial operations for a device */
#define serial_get_ops(dev) ((struct dm_serial_ops *)(dev)->driver->ops)
/**
* serial_getconfig() - Get the uart configuration
* (parity, 5/6/7/8 bits word length, stop bits)
*
* Get a current config for this device.
*
* @dev: Device pointer
* @serial_config: Returns config information (see SERIAL_... above)
* Return: 0 if OK, -ve on error
*/
int serial_getconfig(struct udevice *dev, uint *config);
/**
* serial_setconfig() - Set up the uart configuration
* (parity, 5/6/7/8 bits word length, stop bits)
*
* Set up a new config for this device.
*
* @dev: Device pointer
* @serial_config: number of bits, parity and number of stopbits to use
* Return: 0 if OK, -ve on error
*/
int serial_setconfig(struct udevice *dev, uint config);
/**
* serial_getinfo() - Get serial device information
*
* @dev: Device pointer
* @info: struct serial_device_info to fill
* Return: 0 if OK, -ve on error
*/
int serial_getinfo(struct udevice *dev, struct serial_device_info *info);
void atmel_serial_initialize(void);
void mcf_serial_initialize(void);
void mpc85xx_serial_initialize(void);
void mxc_serial_initialize(void);
void ns16550_serial_initialize(void);
void pl01x_serial_initialize(void);
void pxa_serial_initialize(void);
void sh_serial_initialize(void);
/**
* serial_printf() - Write a formatted string to the serial console
*
* The total size of the output must be less than CONFIG_SYS_PBSIZE.
*
* @fmt: Printf format string, followed by format arguments
* Return: number of characters written
*/
int serial_printf(const char *fmt, ...)
__attribute__ ((format (__printf__, 1, 2)));
int serial_init(void);
void serial_setbrg(void);
void serial_putc(const char ch);
void serial_putc_raw(const char ch);
void serial_puts(const char *str);
#if defined(CONFIG_CONSOLE_FLUSH_SUPPORT) && CONFIG_IS_ENABLED(DM_SERIAL)
void serial_flush(void);
#else
static inline void serial_flush(void) {}
#endif
int serial_getc(void);
int serial_tstc(void);
#endif