diff options
Diffstat (limited to 'src/sam3/sam4_usb.c')
| -rw-r--r-- | src/sam3/sam4_usb.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/src/sam3/sam4_usb.c b/src/sam3/sam4_usb.c new file mode 100644 index 00000000..ecf8e544 --- /dev/null +++ b/src/sam3/sam4_usb.c @@ -0,0 +1,238 @@ +// Hardware interface to SAM4 USB Device Port +// +// 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> // NULL +#include "board/irq.h" // irq_disable +#include "board/usb_cdc.h" // usb_notify_ep0 +#include "board/usb_cdc_ep.h" // USB_CDC_EP_BULK_IN +#include "internal.h" // UDP +#include "sched.h" // DECL_INIT + +#define CSR_EP0 (UDP_CSR_EPTYPE_CTRL | UDP_CSR_EPEDS) +#define CSR_ACM (UDP_CSR_EPTYPE_INT_IN | UDP_CSR_EPEDS) +#define CSR_BULK_OUT (UDP_CSR_EPTYPE_BULK_OUT | UDP_CSR_EPEDS) +#define CSR_BULK_IN (UDP_CSR_EPTYPE_BULK_IN | UDP_CSR_EPEDS) + +static void +usb_write_packet(uint32_t ep, const uint8_t *data, uint32_t len) +{ + while (len--) + UDP->UDP_FDR[ep] = *data++; +} + +static uint32_t +usb_read_packet(uint32_t ep, uint32_t csr, uint8_t *data, uint32_t max_len) +{ + uint32_t pk_len = (csr & UDP_CSR_RXBYTECNT_Msk) >> UDP_CSR_RXBYTECNT_Pos; + uint32_t len = pk_len < max_len ? pk_len : max_len, orig_len = len; + while (len--) + *data++ = UDP->UDP_FDR[ep]; + return orig_len; +} + +int_fast8_t +usb_read_bulk_out(void *data, uint_fast8_t max_len) +{ + static uint32_t next_bk = UDP_CSR_RX_DATA_BK0; + const uint32_t other_irqs = (UDP_CSR_RXSETUP | UDP_CSR_STALLSENT + | UDP_CSR_TXCOMP); + uint32_t csr = UDP->UDP_CSR[USB_CDC_EP_BULK_OUT]; + uint32_t bk = csr & (UDP_CSR_RX_DATA_BK0 | UDP_CSR_RX_DATA_BK1); + if (!bk) { + // Not ready to receive data + if (csr & other_irqs) + UDP->UDP_CSR[USB_CDC_EP_BULK_OUT] = ( + CSR_BULK_OUT | UDP_CSR_RX_DATA_BK0 | UDP_CSR_RX_DATA_BK1); + UDP->UDP_IER = 1<<USB_CDC_EP_BULK_OUT; + return -1; + } + uint32_t len = usb_read_packet(USB_CDC_EP_BULK_OUT, csr, data, max_len); + if (bk == (UDP_CSR_RX_DATA_BK0 | UDP_CSR_RX_DATA_BK1)) + bk = next_bk; + next_bk = bk ^ (UDP_CSR_RX_DATA_BK0 | UDP_CSR_RX_DATA_BK1); + UDP->UDP_CSR[USB_CDC_EP_BULK_OUT] = CSR_BULK_OUT | next_bk; + return len; +} + +int_fast8_t +usb_send_bulk_in(void *data, uint_fast8_t len) +{ + const uint32_t other_irqs = (UDP_CSR_RXSETUP | UDP_CSR_STALLSENT + | UDP_CSR_RX_DATA_BK0 | UDP_CSR_RX_DATA_BK1); + uint32_t csr = UDP->UDP_CSR[USB_CDC_EP_BULK_IN]; + if (csr & UDP_CSR_TXPKTRDY) { + // Not ready to send + if (csr & other_irqs) + UDP->UDP_CSR[USB_CDC_EP_BULK_IN] = CSR_BULK_IN | UDP_CSR_TXCOMP; + UDP->UDP_IER = 1<<USB_CDC_EP_BULK_IN; + return -1; + } + usb_write_packet(USB_CDC_EP_BULK_IN, data, len); + UDP->UDP_CSR[USB_CDC_EP_BULK_IN] = CSR_BULK_IN | UDP_CSR_TXPKTRDY; + return len; +} + +int_fast8_t +usb_read_ep0(void *data, uint_fast8_t max_len) +{ + const uint32_t other_irqs = (UDP_CSR_RXSETUP | UDP_CSR_STALLSENT + | UDP_CSR_TXCOMP | UDP_CSR_RX_DATA_BK1); + uint32_t csr = UDP->UDP_CSR[0]; + if (csr & other_irqs) + return -2; + if (!(csr & UDP_CSR_RX_DATA_BK0)) { + // Not ready to receive data + UDP->UDP_IER = 1<<0; + return -1; + } + uint32_t len = usb_read_packet(0, csr, data, max_len); + if (UDP->UDP_CSR[0] & other_irqs) + return -2; + UDP->UDP_CSR[0] = CSR_EP0 | other_irqs; + return len; +} + +int_fast8_t +usb_read_ep0_setup(void *data, uint_fast8_t max_len) +{ + const uint32_t other_irqs = (UDP_CSR_STALLSENT | UDP_CSR_TXCOMP + | UDP_CSR_RX_DATA_BK0 | UDP_CSR_RX_DATA_BK1); + uint32_t csr = UDP->UDP_CSR[0]; + if (!(csr & UDP_CSR_RXSETUP)) { + // No data ready to read + if (csr & other_irqs) + UDP->UDP_CSR[0] = CSR_EP0 | UDP_CSR_RXSETUP; + UDP->UDP_IER = 1<<0; + return -1; + } + uint32_t len = usb_read_packet(0, csr, data, max_len); + uint32_t dir = *(uint8_t*)data & 0x80 ? UDP_CSR_DIR : 0; + UDP->UDP_CSR[0] = CSR_EP0 | dir; + return len; +} + +int_fast8_t +usb_send_ep0(const void *data, uint_fast8_t len) +{ + const uint32_t other_irqs = (UDP_CSR_RXSETUP | UDP_CSR_STALLSENT + | UDP_CSR_RX_DATA_BK0 | UDP_CSR_RX_DATA_BK1); + uint32_t csr = UDP->UDP_CSR[0]; + if (csr & other_irqs) + return -2; + if (csr & UDP_CSR_TXPKTRDY) { + // Not ready to send + UDP->UDP_IER = 1<<0; + return -1; + } + usb_write_packet(0, data, len); + uint32_t dir = csr & UDP_CSR_DIR; + UDP->UDP_CSR[0] = CSR_EP0 | dir | UDP_CSR_TXPKTRDY | other_irqs; + return len; +} + +void +usb_stall_ep0(void) +{ + UDP->UDP_CSR[0] = CSR_EP0 | UDP_CSR_FORCESTALL; + UDP->UDP_IER = 1<<0; +} + +static uint32_t set_address; + +void +usb_set_address(uint_fast8_t addr) +{ + set_address = addr | UDP_FADDR_FEN; + usb_send_ep0(NULL, 0); + UDP->UDP_IER = 1<<0; +} + +void +usb_set_configure(void) +{ + UDP->UDP_CSR[USB_CDC_EP_ACM] = CSR_ACM; + UDP->UDP_CSR[USB_CDC_EP_BULK_OUT] = CSR_BULK_OUT; + UDP->UDP_CSR[USB_CDC_EP_BULK_IN] = CSR_BULK_IN; + UDP->UDP_GLB_STAT |= UDP_GLB_STAT_CONFG; +} + +#if CONFIG_MACH_SAM4S8C +#define EFC_HW EFC0 +#elif CONFIG_MACH_SAM4E8E +#define EFC_HW EFC +#endif + +void noinline __aligned(16) // align for predictable flash code access +usb_request_bootloader(void) +{ + irq_disable(); + // Request boot from ROM (instead of boot from flash) + while ((EFC_HW->EEFC_FSR & EEFC_FSR_FRDY) == 0) + ; + EFC_HW->EEFC_FCR = (EEFC_FCR_FCMD_CGPB | EEFC_FCR_FARG(1) + | EEFC_FCR_FKEY_PASSWD); + while ((EFC_HW->EEFC_FSR & EEFC_FSR_FRDY) == 0) + ; + // Reboot + RSTC->RSTC_CR = RSTC_CR_KEY(0xA5) | RSTC_CR_PROCRST | RSTC_CR_PERRST; + for (;;) + ; +} + +void +usbserial_init(void) +{ + // Enable clocks + enable_pclock(ID_UDP); + PMC->PMC_USB = PMC_USB_USBDIV(5 - 1); // PLLA=240Mhz; divide by 5 for 48Mhz + PMC->PMC_SCER = PMC_SCER_UDP; + + // Enable USB pullup + UDP->UDP_TXVC = UDP_TXVC_PUON | UDP_TXVC_TXVDIS; + + // Enable interrupts + UDP->UDP_ICR = 0xffffffff; + NVIC_SetPriority(UDP_IRQn, 1); + NVIC_EnableIRQ(UDP_IRQn); +} +DECL_INIT(usbserial_init); + +// Configure endpoint 0 after usb reset completes +static void +handle_end_reset(void) +{ + UDP->UDP_ICR = UDP_ISR_ENDBUSRES; + + UDP->UDP_CSR[0] = CSR_EP0; + UDP->UDP_IER = 1<<0; + + UDP->UDP_TXVC = UDP_TXVC_PUON; +} + +void __visible +UDP_Handler(void) +{ + uint32_t s = UDP->UDP_ISR; + UDP->UDP_IDR = s; + if (s & UDP_ISR_ENDBUSRES) + handle_end_reset(); + if (s & UDP_ISR_RXRSM) + UDP->UDP_ICR = UDP_ISR_RXRSM; + if (s & (1<<0)) { + usb_notify_ep0(); + + if (set_address && UDP->UDP_CSR[0] & UDP_CSR_TXCOMP) { + // Ack from set_address command sent - now update address + UDP->UDP_FADDR = set_address; + UDP->UDP_GLB_STAT |= UDP_GLB_STAT_FADDEN; + set_address = 0; + } + } + if (s & (1<<USB_CDC_EP_BULK_OUT)) + usb_notify_bulk_out(); + if (s & (1<<USB_CDC_EP_BULK_IN)) + usb_notify_bulk_in(); +} |