diff options
Diffstat (limited to 'src/lpc176x')
| -rw-r--r-- | src/lpc176x/Kconfig | 4 | ||||
| -rw-r--r-- | src/lpc176x/Makefile | 1 | ||||
| -rw-r--r-- | src/lpc176x/timer.c | 2 | ||||
| -rw-r--r-- | src/lpc176x/usbserial.c | 297 |
4 files changed, 303 insertions, 1 deletions
diff --git a/src/lpc176x/Kconfig b/src/lpc176x/Kconfig index cdfad6cd..fa80c463 100644 --- a/src/lpc176x/Kconfig +++ b/src/lpc176x/Kconfig @@ -25,7 +25,11 @@ config CLOCK_FREQ default 25000000 if MACH_LPC1768 # 100000000 / 4 default 30000000 if MACH_LPC1769 # 120000000 / 4 +config USBSERIAL + bool "Use USB for communication (instead of serial)" + default y config SERIAL + depends on !USBSERIAL bool default y config SERIAL_BAUD diff --git a/src/lpc176x/Makefile b/src/lpc176x/Makefile index 2ff7d174..94e6a268 100644 --- a/src/lpc176x/Makefile +++ b/src/lpc176x/Makefile @@ -17,6 +17,7 @@ src-y += lpc176x/main.c lpc176x/timer.c lpc176x/gpio.c src-y += generic/crc16_ccitt.c generic/alloc.c src-y += generic/armcm_irq.c generic/timer_irq.c src-y += ../lib/lpc176x/device/system_LPC17xx.c +src-$(CONFIG_USBSERIAL) += lpc176x/usbserial.c generic/usb_cdc.c src-$(CONFIG_SERIAL) += lpc176x/serial.c generic/serial_irq.c # Add the TOOLCHAIN_GCC_ARM files to the build diff --git a/src/lpc176x/timer.c b/src/lpc176x/timer.c index d6d6f9ed..d8196329 100644 --- a/src/lpc176x/timer.c +++ b/src/lpc176x/timer.c @@ -38,7 +38,7 @@ timer_init(void) // Disable timer LPC_TIM0->TCR = 0x02; // Enable interrupts - NVIC_SetPriority(TIMER0_IRQn, 1); + NVIC_SetPriority(TIMER0_IRQn, 2); NVIC_EnableIRQ(TIMER0_IRQn); LPC_TIM0->MCR = 0x01; // Clear counter value diff --git a/src/lpc176x/usbserial.c b/src/lpc176x/usbserial.c new file mode 100644 index 00000000..28c0881f --- /dev/null +++ b/src/lpc176x/usbserial.c @@ -0,0 +1,297 @@ +// Hardware interface to USB on lpc176x +// +// Copyright (C) 2018 Kevin O'Connor <kevin@koconnor.net> +// +// This file may be distributed under the terms of the GNU GPLv3 license. + +#include <string.h> // memcpy +#include "LPC17xx.h" // LPC_SC +#include "board/usb_cdc.h" // usb_notify_setup +#include "byteorder.h" // cpu_to_le32 +#include "command.h" // output +#include "internal.h" // gpio_peripheral +#include "sched.h" // DECL_INIT + +// Internal endpoint addresses +#define EP0OUT 0x00 +#define EP0IN 0x01 +#define EP1IN 0x03 +#define EP2OUT 0x04 +#define EP5IN 0x0b + +// USB device interupt status flags +#define EP_SLOW (1<<2) +#define DEV_STAT (1<<3) +#define CCEMPTY (1<<4) +#define CDFULL (1<<5) +#define EP_RLZED (1<<8) + +#define RD_EN (1<<0) +#define WR_EN (1<<1) + +static void +usb_irq_disable(void) +{ + NVIC_DisableIRQ(USB_IRQn); +} + +static void +usb_irq_enable(void) +{ + NVIC_EnableIRQ(USB_IRQn); +} + +static void +usb_wait(uint32_t flag) +{ + while (!(LPC_USB->USBDevIntSt & flag)) + ; + LPC_USB->USBDevIntClr = flag; +} + + +/**************************************************************** + * Serial Interface Engine (SIE) functions + ****************************************************************/ + +#define SIE_CMD_SELECT 0x00 +#define SIE_CMD_SET_ENDPOINT_STATUS 0x40 +#define SIE_CMD_SET_ADDRESS 0xD0 +#define SIE_CMD_CONFIGURE 0xD8 +#define SIE_CMD_SET_DEVICE_STATUS 0xFE +#define SIE_CMD_CLEAR_BUFFER 0xF2 +#define SIE_CMD_VALIDATE_BUFFER 0xFA + +static void +sie_cmd(uint32_t cmd) +{ + LPC_USB->USBDevIntClr = CDFULL | CCEMPTY; + LPC_USB->USBCmdCode = 0x00000500 | (cmd << 16); + usb_wait(CCEMPTY); +} + +static void +sie_cmd_write(uint32_t cmd, uint32_t data) +{ + sie_cmd(cmd); + LPC_USB->USBCmdCode = 0x00000100 | (data << 16); + usb_wait(CCEMPTY); +} + +static uint32_t +sie_cmd_read(uint32_t cmd) +{ + sie_cmd(cmd); + LPC_USB->USBCmdCode = 0x00000200 | (cmd << 16); + usb_wait(CDFULL); + return LPC_USB->USBCmdData; +} + +static uint32_t +sie_select_and_clear(uint32_t idx) +{ + LPC_USB->USBEpIntClr = 1<<idx; + usb_wait(CDFULL); + return LPC_USB->USBCmdData; +} + + +/**************************************************************** + * Interface + ****************************************************************/ + +static int_fast8_t +usb_write_packet(uint32_t ep, const void *data, uint_fast8_t len) +{ + usb_irq_disable(); + uint32_t sts = sie_cmd_read(SIE_CMD_SELECT | ep); + if (sts & 0x01) { + // Output buffers full + usb_irq_enable(); + return -1; + } + + LPC_USB->USBCtrl = WR_EN | ((ep/2) << 2); + LPC_USB->USBTxPLen = len; + if (!len) + LPC_USB->USBTxData = 0; + int i; + for (i = 0; i<DIV_ROUND_UP(len, 4); i++) { + uint32_t d; + memcpy(&d, data, sizeof(d)); + data += sizeof(d); + LPC_USB->USBTxData = cpu_to_le32(d); + } + sie_cmd(SIE_CMD_VALIDATE_BUFFER); + usb_irq_enable(); + + return len; +} + +static int_fast8_t +usb_read_packet(uint32_t ep, void *data, uint_fast8_t max_len) +{ + usb_irq_disable(); + uint32_t sts = sie_cmd_read(SIE_CMD_SELECT | ep); + if (!(sts & 0x01)) { + // No data available + usb_irq_enable(); + return -1; + } + + // Determine packet size + LPC_USB->USBCtrl = RD_EN | ((ep/2) << 2); + uint32_t plen = LPC_USB->USBRxPLen; + while (!(plen & (1<<11))) + plen = LPC_USB->USBRxPLen; + plen &= 0x3FF; + if (plen > max_len) + // XXX - return error code? must keep reading? + plen = max_len; + // Copy data + uint32_t xfer = plen; + for (;;) { + uint32_t d = le32_to_cpu(LPC_USB->USBRxData); + if (xfer <= sizeof(d)) { + memcpy(data, &d, xfer); + break; + } + memcpy(data, &d, sizeof(d)); + data += sizeof(d); + xfer -= sizeof(d); + } + // Clear space for next packet + sts = sie_cmd_read(SIE_CMD_CLEAR_BUFFER); + usb_irq_enable(); + if (sts & 0x01) + // Packet overwritten + return -1; + + return plen; +} + +int_fast8_t +usb_read_bulk_out(void *data, uint_fast8_t max_len) +{ + return usb_read_packet(EP2OUT, data, max_len); +} + +int_fast8_t +usb_send_bulk_in(void *data, uint_fast8_t len) +{ + return usb_write_packet(EP5IN, data, len); +} + +int_fast8_t +usb_read_setup(void *data, uint_fast8_t max_len) +{ + return usb_read_packet(EP0OUT, data, max_len); +} + +int_fast8_t +usb_send_setup(const void *data, uint_fast8_t len) +{ + return usb_write_packet(EP0IN, data, len); +} + +void +usb_set_stall(void) +{ + usb_irq_disable(); + sie_cmd_write(SIE_CMD_SET_ENDPOINT_STATUS | 0, (1<<7)); + usb_irq_enable(); +} + +void +usb_set_address(uint_fast8_t addr) +{ + usb_irq_disable(); + sie_cmd_write(SIE_CMD_SET_ADDRESS, addr | (1<<7)); + usb_irq_enable(); + usb_send_setup(NULL, 0); +} + +static void +realize_endpoint(uint32_t idx, uint32_t packet_size) +{ + LPC_USB->USBDevIntClr = EP_RLZED; + LPC_USB->USBReEp |= 1<<idx; + LPC_USB->USBEpInd = idx; + LPC_USB->USBMaxPSize = packet_size; + usb_wait(EP_RLZED); + LPC_USB->USBEpIntEn |= 1<<idx; + sie_cmd_write(SIE_CMD_SET_ENDPOINT_STATUS | idx, 0); +} + +void +usb_set_configure(void) +{ + usb_irq_disable(); + realize_endpoint(EP1IN, USB_CDC_EP_ACM_SIZE); + realize_endpoint(EP2OUT, USB_CDC_EP_BULK_OUT_SIZE); + realize_endpoint(EP5IN, USB_CDC_EP_BULK_IN_SIZE); + sie_cmd_write(SIE_CMD_CONFIGURE, 1); + usb_irq_enable(); +} + +void +usbserial_init(void) +{ + usb_irq_disable(); + // enable power + LPC_SC->PCONP |= (1<<31); + // enable clock + LPC_USB->USBClkCtrl = 0x12; + while (LPC_USB->USBClkSt != 0x12) + ; + // configure USBD+, USBD-, and USB Connect pins + gpio_peripheral(0, 29, 1, 0); + gpio_peripheral(0, 30, 1, 0); + gpio_peripheral(2, 9, 1, 0); + // setup endpoints + realize_endpoint(EP0OUT, USB_CDC_EP0_SIZE); + realize_endpoint(EP0IN, USB_CDC_EP0_SIZE); + sie_cmd_write(SIE_CMD_SET_DEVICE_STATUS, 1); + // enable irqs + LPC_USB->USBDevIntEn = DEV_STAT | EP_SLOW; + NVIC_SetPriority(USB_IRQn, 1); + usb_irq_enable(); +} +DECL_INIT(usbserial_init); + +void +usbserial_shutdown(void) +{ + usb_irq_enable(); +} +DECL_SHUTDOWN(usbserial_shutdown); + +void __visible +USB_IRQHandler(void) +{ + uint32_t udis = LPC_USB->USBDevIntSt; + if (udis & DEV_STAT) { + LPC_USB->USBDevIntClr = DEV_STAT; + // XXX - should handle reset and other states + } + if (udis & EP_SLOW) { + uint32_t ueis = LPC_USB->USBEpIntSt; + if (ueis & (1<<EP0OUT)) { + sie_select_and_clear(EP0OUT); + usb_notify_setup(); + } + if (ueis & (1<<EP0IN)) { + sie_select_and_clear(EP0IN); + usb_notify_setup(); + } + if (ueis & (1<<EP2OUT)) { + sie_select_and_clear(EP2OUT); + usb_notify_bulk_out(); + } + if (ueis & (1<<EP5IN)) { + sie_select_and_clear(EP5IN); + usb_notify_bulk_in(); + } + LPC_USB->USBDevIntClr = EP_SLOW; + } +} |