diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/rp2040/usbserial.c | 102 |
1 files changed, 99 insertions, 3 deletions
diff --git a/src/rp2040/usbserial.c b/src/rp2040/usbserial.c index 3a6736ef..83838d2d 100644 --- a/src/rp2040/usbserial.c +++ b/src/rp2040/usbserial.c @@ -7,9 +7,13 @@ #include <string.h> // memcpy #include "board/armcm_boot.h" // armcm_enable_irq #include "board/io.h" // writeb +#include "board/misc.h" // timer_read_time #include "board/usb_cdc.h" // usb_notify_ep0 #include "board/usb_cdc_ep.h" // USB_CDC_EP_BULK_IN #include "board/usbstd.h" // USB_ENDPOINT_XFER_INT +#include "hardware/regs/sysinfo.h" // SYSINFO_CHIP_ID_OFFSET +#include "hardware/structs/iobank0.h" // iobank0_hw +#include "hardware/structs/padsbank0.h" // padsbank0_hw #include "hardware/structs/resets.h" // RESETS_RESET_USBCTRL_BITS #include "hardware/structs/usb.h" // usb_hw #include "internal.h" // enable_pclock @@ -165,6 +169,89 @@ usb_request_bootloader(void) /**************************************************************** + * USB Errata workaround + ****************************************************************/ + +// The rp2040 USB has an errata causing it to sometimes not connect +// after a reset. The following code has extracts from the PICO SDK. + +static struct task_wake usb_errata_wake; + +// Workaround for rp2040-e5 errata +void +usb_errata_task(void) +{ + if (!sched_check_wake(&usb_errata_wake)) + return; + + if (usb_hw->sie_status & USB_SIE_STATUS_CONNECTED_BITS) + // Already connected - workaround not needed + return; + + // Wait for not in SE0 state + if (!(usb_hw->sie_status & USB_SIE_STATUS_LINE_STATE_BITS)) { + sched_wake_task(&usb_errata_wake); + return; + } + + // Backup GPIO15 pad state + uint32_t dp = 15; + uint32_t gpio_ctrl_prev = iobank0_hw->io[dp].ctrl; + uint32_t pad_ctrl_prev = padsbank0_hw->io[dp]; + + // Enable bus keep + hw_write_masked(&padsbank0_hw->io[dp], + PADS_BANK0_GPIO15_PUE_BITS | PADS_BANK0_GPIO15_PDE_BITS, + PADS_BANK0_GPIO15_PUE_BITS | PADS_BANK0_GPIO15_PDE_BITS); + // Disable pad output + hw_write_masked(&iobank0_hw->io[dp].ctrl, + 0x2 << IO_BANK0_GPIO15_CTRL_OEOVER_LSB, + IO_BANK0_GPIO15_CTRL_OEOVER_BITS); + // Enable USB debug muxing function + hw_write_masked(&iobank0_hw->io[dp].ctrl, + 8 << IO_BANK0_GPIO15_CTRL_FUNCSEL_LSB, + IO_BANK0_GPIO15_CTRL_FUNCSEL_BITS); + // Set input override + hw_write_masked(&iobank0_hw->io[dp].ctrl, + 0x3 << IO_BANK0_GPIO15_CTRL_INOVER_LSB, + IO_BANK0_GPIO15_CTRL_INOVER_BITS); + // PHY pullups need to stay on + hw_set_alias(usb_hw)->phy_direct = USB_USBPHY_DIRECT_DP_PULLUP_EN_BITS; + hw_set_alias(usb_hw)->phy_direct_override = + USB_USBPHY_DIRECT_OVERRIDE_DP_PULLUP_EN_OVERRIDE_EN_BITS; + // Switch from USB PHY to GPIO PHY, now with J forced + usb_hw->muxing = (USB_USB_MUXING_TO_DIGITAL_PAD_BITS + | USB_USB_MUXING_SOFTCON_BITS); + + // Wait 1ms + uint32_t endtime = timer_read_time() + timer_from_us(1000); + while (timer_is_before(timer_read_time(), endtime)) + ; + + // Verify in connected state + endtime += timer_from_us(1000); + for (;;) { + if (usb_hw->sie_status & USB_SIE_STATUS_CONNECTED_BITS) + break; + if (timer_is_before(endtime, timer_read_time())) + // Something went wrong - restore state and continue anyway + break; + } + + // Switch back to USB phy + usb_hw->muxing = USB_USB_MUXING_TO_PHY_BITS | USB_USB_MUXING_SOFTCON_BITS; + // Unset PHY pullup overrides + hw_clear_alias(usb_hw)->phy_direct_override = + USB_USBPHY_DIRECT_OVERRIDE_DP_PULLUP_EN_OVERRIDE_EN_BITS; + + // Restore GPIO control states + iobank0_hw->io[dp].ctrl = gpio_ctrl_prev; + padsbank0_hw->io[dp] = pad_ctrl_prev; +} +DECL_TASK(usb_errata_task); + + +/**************************************************************** * Setup and interrupts ****************************************************************/ @@ -191,6 +278,10 @@ USB_Handler(void) } } } + if (ints & USB_INTS_BUS_RESET_BITS) { + usb_hw->sie_status = USB_SIE_STATUS_BUS_RESET_BITS; + sched_wake_task(&usb_errata_wake); + } } static void @@ -228,15 +319,20 @@ usbserial_init(void) | USB_USB_PWR_VBUS_DETECT_OVERRIDE_EN_BITS); usb_hw->main_ctrl = USB_MAIN_CTRL_CONTROLLER_EN_BITS; + // Check if usb errata workaround needed + enable_pclock(RESETS_RESET_SYSINFO_BITS); + uint32_t chip_id = *((io_ro_32*)(SYSINFO_BASE + SYSINFO_CHIP_ID_OFFSET)); + uint32_t version = ((chip_id & SYSINFO_CHIP_ID_REVISION_BITS) + >> SYSINFO_CHIP_ID_REVISION_LSB); + // Enable irqs usb_hw->sie_ctrl = USB_SIE_CTRL_EP0_INT_1BUF_BITS; - usb_hw->inte = USB_INTE_BUFF_STATUS_BITS | USB_INTE_SETUP_REQ_BITS; + usb_hw->inte = (USB_INTE_BUFF_STATUS_BITS | USB_INTE_SETUP_REQ_BITS + | (version == 1 ? USB_INTE_BUS_RESET_BITS: 0)); armcm_enable_irq(USB_Handler, USBCTRL_IRQ_IRQn, 1); // Enable USB pullup usb_hw->sie_ctrl = (USB_SIE_CTRL_EP0_INT_1BUF_BITS | USB_SIE_CTRL_PULLUP_EN_BITS); - - // XXX - errata reset workaround?? } DECL_INIT(usbserial_init); |