usb: dwc3: invalidate dcache on buffer used in interrupt handling

On Qualcomm systems, the setup buffer and even buffers are in
a bad state at interrupt handling, so invalidate the dcache lines
for the setup_buf and event buffer to make sure we read correct
data written by the hardware.

This fixes the following error:
dwc3-generic-peripheral usb@a600000: UNKNOWN IRQ type -1
dwc3-generic-peripheral usb@a600000: UNKNOWN IRQ type 4673109

and invalid situation in dwc3_gadget_giveback() because setup_buf content
is read at 0s and leads to fatal crash fixed by [1].

[1] https://lore.kernel.org/all/20240528-topic-sm8x50-dwc3-gadget-crash-fix-v1-1-58434ab4b3d3@linaro.org/

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20241011-u-boot-dwc3-gadget-dcache-fixup-v4-3-5f3498d8035b@linaro.org
Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 8ba5fcd5312cdcb39d3fc3bea3272e1eab06e7c2..531f0b522af71b38acd8e7f727d86fded57443b7 100644 (file)
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -742,6 +742,8 @@ static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
        if (!dwc->gadget_driver)
                goto out;
 
+       dwc3_invalidate_cache((uintptr_t)ctrl, sizeof(*ctrl));
+
        len = le16_to_cpu(ctrl->wLength);
        if (!len) {
                dwc->three_stage_setup = false;

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 19c3a5f5e58f05081d5bf71be4c095e4508743a4..e5a383407a2eed9cd3a7db16ca0f326e62633c8f 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2534,6 +2534,8 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3 *dwc, u32 buf)
        while (left > 0) {
                union dwc3_event event;
 
+               dwc3_invalidate_cache((uintptr_t)evt->buf, evt->length);
+
                event.raw = *(u32 *) (evt->buf + evt->lpos);
 
                dwc3_process_event_entry(dwc, &event);

diff --git a/drivers/usb/dwc3/io.h b/drivers/usb/dwc3/io.h
index 0ede323671b4775402c1536c1352bca8bf27f250..c1ab02881424b10e0eadf6e0c97f2c904ddb762f 100644 (file)
--- a/drivers/usb/dwc3/io.h
+++ b/drivers/usb/dwc3/io.h
@@ -55,4 +55,12 @@ static inline void dwc3_flush_cache(uintptr_t addr, int length)
 
        flush_dcache_range((unsigned long)start_addr, (unsigned long)end_addr);
 }
+
+static inline void dwc3_invalidate_cache(uintptr_t addr, int length)
+{
+       uintptr_t start_addr = (uintptr_t)addr & ~(CACHELINE_SIZE - 1);
+       uintptr_t end_addr = ALIGN((uintptr_t)addr + length, CACHELINE_SIZE);
+
+       invalidate_dcache_range((unsigned long)start_addr, (unsigned long)end_addr);
+}
 #endif /* __DRIVERS_USB_DWC3_IO_H */