diff options
Diffstat (limited to 'drivers/serial/serial_efi.c')
-rw-r--r-- | drivers/serial/serial_efi.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/drivers/serial/serial_efi.c b/drivers/serial/serial_efi.c new file mode 100644 index 0000000000..f0a2b22c2b --- /dev/null +++ b/drivers/serial/serial_efi.c @@ -0,0 +1,221 @@ +/* + * Copyright (C) 2017 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> + * + * Under GPLv2 Only + */ + +#include <common.h> +#include <driver.h> +#include <init.h> +#include <malloc.h> +#include <efi.h> +#include <efi/efi.h> +#include <efi/efi-device.h> + +/* + * define for Control bits, grouped by read only, write only, and read write + * + * Read Only + */ +#define EFI_SERIAL_CLEAR_TO_SEND 0x00000010 +#define EFI_SERIAL_DATA_SET_READY 0x00000020 +#define EFI_SERIAL_RING_INDICATE 0x00000040 +#define EFI_SERIAL_CARRIER_DETECT 0x00000080 +#define EFI_SERIAL_INPUT_BUFFER_EMPTY 0x00000100 +#define EFI_SERIAL_OUTPUT_BUFFER_EMPTY 0x00000200 + +/* + * Write Only + */ +#define EFI_SERIAL_REQUEST_TO_SEND 0x00000002 +#define EFI_SERIAL_DATA_TERMINAL_READY 0x00000001 + +/* + * Read Write + */ +#define EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE 0x00001000 +#define EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE 0x00002000 +#define EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE 0x00004000 + +typedef enum { + DefaultParity, + NoParity, + EvenParity, + OddParity, + MarkParity, + SpaceParity +} efi_parity_type; + +typedef enum { + DefaultStopBits, + OneStopBit, + OneFiveStopBits, + TwoStopBits +} efi_stop_bits_type; + +struct efi_serial_io_mode { + uint32_t controlmask; + uint32_t timeout; + uint64_t baudrate; + uint32_t receivefifodepth; + uint32_t databits; + uint32_t parity; + uint32_t stopbits; +}; + +struct efi_serial_io_protocol { + uint32_t revision; + + efi_status_t (EFIAPI *reset) (struct efi_serial_io_protocol *This); + efi_status_t (EFIAPI *set_attributes) (struct efi_serial_io_protocol *This, + uint64_t baudrate, uint32_t receivefifodepth, + uint32_t timeout, efi_parity_type parity, + uint8_t databits, efi_stop_bits_type stopbits); + efi_status_t (EFIAPI *setcontrol) (struct efi_serial_io_protocol *This, + uint32_t control); + efi_status_t (EFIAPI *getcontrol) (struct efi_serial_io_protocol *This, + uint32_t *control); + efi_status_t (EFIAPI *write) (struct efi_serial_io_protocol *This, + unsigned long *buffersize, void *buffer); + efi_status_t (EFIAPI *read) (struct efi_serial_io_protocol *This, + unsigned long *buffersize, void *buffer); + + struct efi_serial_io_mode *mode; +}; + +/* + * We wrap our port structure around the generic console_device. + */ +struct efi_serial_port { + struct efi_serial_io_protocol *serial; + struct console_device uart; /* uart */ + struct efi_device *efidev; +}; + +static inline struct efi_serial_port * +to_efi_serial_port(struct console_device *uart) +{ + return container_of(uart, struct efi_serial_port, uart); +} + +static int efi_serial_setbaudrate(struct console_device *cdev, int baudrate) +{ + struct efi_serial_port *uart = to_efi_serial_port(cdev); + struct efi_serial_io_protocol *serial = uart->serial; + efi_status_t efiret; + + efiret = serial->set_attributes(serial, baudrate, 0, 0, NoParity, 8, + OneStopBit); + if (EFI_ERROR(efiret)) + return -efi_errno(efiret); + + return 0; +} + +static void efi_serial_putc(struct console_device *cdev, char c) +{ + struct efi_serial_port *uart = to_efi_serial_port(cdev); + struct efi_serial_io_protocol *serial = uart->serial; + uint32_t control; + efi_status_t efiret; + unsigned long buffersize = sizeof(char); + + do { + efiret = serial->getcontrol(serial, &control); + if (EFI_ERROR(efiret)) + return; + + } while(!(control & EFI_SERIAL_CLEAR_TO_SEND)); + + serial->write(serial, &buffersize, &c); +} + +static int efi_serial_puts(struct console_device *cdev, const char *s) +{ + struct efi_serial_port *uart = to_efi_serial_port(cdev); + struct efi_serial_io_protocol *serial = uart->serial; + uint32_t control; + efi_status_t efiret; + unsigned long buffersize = strlen(s) * sizeof(char); + + do { + efiret = serial->getcontrol(serial, &control); + if (EFI_ERROR(efiret)) + return 0; + + } while(!(control & EFI_SERIAL_CLEAR_TO_SEND)); + + serial->write(serial, &buffersize, (void*)s); + + return strlen(s); +} + +static int efi_serial_getc(struct console_device *cdev) +{ + struct efi_serial_port *uart = to_efi_serial_port(cdev); + struct efi_serial_io_protocol *serial = uart->serial; + uint32_t control; + efi_status_t efiret; + unsigned long buffersize = sizeof(char); + char c; + + do { + efiret = serial->getcontrol(serial, &control); + if (EFI_ERROR(efiret)) + return (int)-1; + + } while(!(control & EFI_SERIAL_DATA_SET_READY)); + + serial->read(serial, &buffersize, &c); + + return (int)c; +} + +static int efi_serial_tstc(struct console_device *cdev) +{ + struct efi_serial_port *uart = to_efi_serial_port(cdev); + struct efi_serial_io_protocol *serial = uart->serial; + uint32_t control; + efi_status_t efiret; + + efiret = serial->getcontrol(serial, &control); + if (EFI_ERROR(efiret)) + return 0; + + return !(control & EFI_SERIAL_INPUT_BUFFER_EMPTY); +} + +static int efi_serial_probe(struct efi_device *efidev) +{ + struct efi_serial_port *uart; + struct console_device *cdev; + + uart = xzalloc(sizeof(struct efi_serial_port)); + + cdev = &uart->uart; + cdev->dev = &efidev->dev; + cdev->tstc = efi_serial_tstc; + cdev->putc = efi_serial_putc; + cdev->puts = efi_serial_puts; + cdev->getc = efi_serial_getc; + cdev->setbrg = efi_serial_setbaudrate; + + uart->serial = efidev->protocol; + + uart->serial->reset(uart->serial); + + /* Enable UART */ + + console_register(cdev); + + return 0; +} + +static struct efi_driver efi_serial_driver = { + .driver = { + .name = "efi-serial", + }, + .probe = efi_serial_probe, + .guid = EFI_SERIAL_IO_PROTOCOL_GUID, +}; +device_efi_driver(efi_serial_driver); |