klipper/src/stm32/usbfs.c

303 lines
8.2 KiB
C

// Hardware interface to "fullspeed USB controller" on stm32f1
//
// Copyright (C) 2018-2019 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include <string.h> // NULL
#include "autoconf.h" // CONFIG_STM32_FLASH_START_2000
#include "board/armcm_boot.h" // armcm_enable_irq
#include "board/armcm_timer.h" // udelay
#include "board/gpio.h" // gpio_out_setup
#include "board/io.h" // writeb
#include "board/usb_cdc.h" // usb_notify_ep0
#include "board/usb_cdc_ep.h" // USB_CDC_EP_BULK_IN
#include "command.h" // DECL_CONSTANT_STR
#include "internal.h" // GPIO
#include "sched.h" // DECL_INIT
/****************************************************************
* USB transfer memory
****************************************************************/
#if CONFIG_MACH_STM32F103
typedef volatile uint32_t epmword_t;
#else
typedef volatile uint16_t epmword_t;
#endif
struct ep_desc {
epmword_t addr_tx, count_tx, addr_rx, count_rx;
};
struct ep_mem {
struct ep_desc ep0, ep_acm, ep_bulk_out, ep_bulk_in;
epmword_t ep0_tx[USB_CDC_EP0_SIZE / 2];
epmword_t ep0_rx[USB_CDC_EP0_SIZE / 2 + 1];
epmword_t ep_acm_tx[USB_CDC_EP_ACM_SIZE / 2];
epmword_t ep_bulk_out_rx[USB_CDC_EP_BULK_OUT_SIZE / 2 + 1];
epmword_t ep_bulk_in_tx[USB_CDC_EP_BULK_IN_SIZE / 2];
};
#define EPM ((struct ep_mem *)USB_PMAADDR)
#define CALC_ADDR(p) (((epmword_t*)(p) - (epmword_t*)EPM) * 2)
#define CALC_SIZE(s) ((s) > 32 ? (DIV_ROUND_UP((s), 32) << 10) | 0x8000 \
: DIV_ROUND_UP((s), 2) << 10)
// Setup the transfer descriptors in dedicated usb memory
static void
btable_configure(void)
{
EPM->ep0.count_tx = 0;
EPM->ep0.addr_tx = CALC_ADDR(EPM->ep0_tx);
EPM->ep0.count_rx = CALC_SIZE(USB_CDC_EP0_SIZE);
EPM->ep0.addr_rx = CALC_ADDR(EPM->ep0_rx);
EPM->ep_acm.count_tx = 0;
EPM->ep_acm.addr_tx = CALC_ADDR(EPM->ep_acm_tx);
EPM->ep_bulk_out.count_rx = CALC_SIZE(USB_CDC_EP_BULK_OUT_SIZE);
EPM->ep_bulk_out.addr_rx = CALC_ADDR(EPM->ep_bulk_out_rx);
EPM->ep_bulk_in.count_tx = 0;
EPM->ep_bulk_in.addr_tx = CALC_ADDR(EPM->ep_bulk_in_tx);
}
// Read a packet stored in dedicated usb memory
static void
btable_read_packet(uint8_t *dest, epmword_t *src, int count)
{
uint_fast8_t i;
for (i=0; i<(count/2); i++) {
uint32_t d = *src++;
*dest++ = d;
*dest++ = d >> 8;
}
if (count & 1)
*dest = *src;
}
// Write a packet to dedicated usb memory
static void
btable_write_packet(epmword_t *dest, const uint8_t *src, int count)
{
int i;
for (i=0; i<(count/2); i++) {
uint8_t b1 = *src++, b2 = *src++;
*dest++ = b1 | (b2 << 8);
}
if (count & 1)
*dest = *src;
}
/****************************************************************
* USB endpoint register
****************************************************************/
#define USB_EPR ((volatile uint32_t *)USB_BASE)
#define EPR_RWBITS (USB_EPADDR_FIELD | USB_EP_KIND | USB_EP_TYPE_MASK)
#define EPR_RWCBITS (USB_EP_CTR_RX | USB_EP_CTR_TX)
static uint32_t
set_stat_rx_bits(uint32_t epr, uint32_t bits)
{
return ((epr & (EPR_RWBITS | USB_EPRX_STAT)) ^ bits) | EPR_RWCBITS;
}
static uint32_t
set_stat_tx_bits(uint32_t epr, uint32_t bits)
{
return ((epr & (EPR_RWBITS | USB_EPTX_STAT)) ^ bits) | EPR_RWCBITS;
}
static uint32_t
set_stat_rxtx_bits(uint32_t epr, uint32_t bits)
{
uint32_t mask = EPR_RWBITS | USB_EPRX_STAT | USB_EPTX_STAT;
return ((epr & mask) ^ bits) | EPR_RWCBITS;
}
/****************************************************************
* USB interface
****************************************************************/
int_fast8_t
usb_read_bulk_out(void *data, uint_fast8_t max_len)
{
uint32_t epr = USB_EPR[USB_CDC_EP_BULK_OUT];
if ((epr & USB_EPRX_STAT) == USB_EP_RX_VALID)
// No data ready
return -1;
uint32_t count = EPM->ep_bulk_out.count_rx & 0x3ff;
if (count > max_len)
count = max_len;
btable_read_packet(data, EPM->ep_bulk_out_rx, count);
USB_EPR[USB_CDC_EP_BULK_OUT] = set_stat_rx_bits(epr, USB_EP_RX_VALID);
return count;
}
int_fast8_t
usb_send_bulk_in(void *data, uint_fast8_t len)
{
uint32_t epr = USB_EPR[USB_CDC_EP_BULK_IN];
if ((epr & USB_EPTX_STAT) != USB_EP_TX_NAK)
// No buffer space available
return -1;
btable_write_packet(EPM->ep_bulk_in_tx, data, len);
EPM->ep_bulk_in.count_tx = len;
USB_EPR[USB_CDC_EP_BULK_IN] = set_stat_tx_bits(epr, USB_EP_TX_VALID);
return len;
}
int_fast8_t
usb_read_ep0(void *data, uint_fast8_t max_len)
{
uint32_t epr = USB_EPR[0];
if ((epr & USB_EPRX_STAT) != USB_EP_RX_NAK)
// No data ready
return -1;
uint32_t count = EPM->ep0.count_rx & 0x3ff;
if (count > max_len)
count = max_len;
btable_read_packet(data, EPM->ep0_rx, count);
USB_EPR[0] = set_stat_rxtx_bits(epr, USB_EP_RX_VALID | USB_EP_TX_NAK);
return count;
}
int_fast8_t
usb_read_ep0_setup(void *data, uint_fast8_t max_len)
{
return usb_read_ep0(data, max_len);
}
int_fast8_t
usb_send_ep0(const void *data, uint_fast8_t len)
{
uint32_t epr = USB_EPR[0];
if ((epr & USB_EPRX_STAT) != USB_EP_RX_VALID)
// Transfer interrupted
return -2;
if ((epr & USB_EPTX_STAT) != USB_EP_TX_NAK)
// No buffer space available
return -1;
btable_write_packet(EPM->ep0_tx, data, len);
EPM->ep0.count_tx = len;
USB_EPR[0] = set_stat_tx_bits(epr, USB_EP_TX_VALID);
return len;
}
void
usb_stall_ep0(void)
{
USB_EPR[0] = set_stat_rxtx_bits(USB_EPR[0]
, USB_EP_RX_STALL | USB_EP_TX_STALL);
}
static uint8_t set_address;
void
usb_set_address(uint_fast8_t addr)
{
writeb(&set_address, addr | USB_DADDR_EF);
usb_send_ep0(NULL, 0);
}
void
usb_set_configure(void)
{
}
/****************************************************************
* Setup and interrupts
****************************************************************/
// Configure interface after a USB reset event
static void
usb_reset(void)
{
USB_EPR[0] = 0 | USB_EP_CONTROL | USB_EP_RX_VALID | USB_EP_TX_NAK;
USB_EPR[USB_CDC_EP_ACM] = (USB_CDC_EP_ACM | USB_EP_INTERRUPT
| USB_EP_RX_NAK | USB_EP_TX_NAK);
USB_EPR[USB_CDC_EP_BULK_OUT] = (USB_CDC_EP_BULK_OUT | USB_EP_BULK
| USB_EP_RX_VALID | USB_EP_TX_NAK);
USB_EPR[USB_CDC_EP_BULK_IN] = (USB_CDC_EP_BULK_IN | USB_EP_BULK
| USB_EP_RX_NAK | USB_EP_TX_NAK);
USB->CNTR = USB_CNTR_CTRM | USB_CNTR_RESETM;
USB->DADDR = USB_DADDR_EF;
}
// Main irq handler
void
USB_IRQHandler(void)
{
uint32_t istr = USB->ISTR;
if (istr & USB_ISTR_CTR) {
// Endpoint activity
uint32_t ep = istr & USB_ISTR_EP_ID;
uint32_t epr = USB_EPR[ep];
USB_EPR[ep] = epr & EPR_RWBITS;
if (ep == 0) {
usb_notify_ep0();
if (epr & USB_EP_CTR_TX && set_address) {
// Apply address after last "in" message transmitted
USB->DADDR = set_address;
set_address = 0;
}
} else if (ep == USB_CDC_EP_BULK_OUT) {
usb_notify_bulk_out();
} else if (ep == USB_CDC_EP_BULK_IN) {
usb_notify_bulk_in();
}
}
if (istr & USB_ISTR_RESET) {
// USB Reset
USB->ISTR = (uint16_t)~USB_ISTR_RESET;
usb_reset();
}
}
DECL_CONSTANT_STR("RESERVE_PINS_USB", "PA11,PA12");
// Initialize the usb controller
void
usb_init(void)
{
if (CONFIG_MACH_STM32F1) {
// Pull the D+ pin low briefly to signal a new connection
gpio_out_setup(GPIO('A', 12), 0);
udelay(5000);
gpio_in_setup(GPIO('A', 12), 0);
}
// Enable USB clock
enable_pclock(USB_BASE);
// Setup USB packet memory
btable_configure();
// Enable USB pullup
#ifdef USB_BCDR_DPPU
USB->BCDR = USB_BCDR_DPPU;
#endif
// Reset usb controller and enable interrupts
USB->CNTR = USB_CNTR_FRES;
USB->BTABLE = 0;
USB->DADDR = 0;
USB->CNTR = USB_CNTR_RESETM;
USB->ISTR = 0;
#if CONFIG_MACH_STM32F103
armcm_enable_irq(USB_IRQHandler, USB_LP_IRQn, 1);
#elif CONFIG_MACH_STM32F0
armcm_enable_irq(USB_IRQHandler, USB_IRQn, 1);
#endif
}
DECL_INIT(usb_init);