From 72357cdb20ee7dca5a19d02ce9b7f14d237fb29e Mon Sep 17 00:00:00 2001
From: Maxime Vincent <maxime@veemax.be>
Date: Fri, 11 Apr 2025 12:15:56 +0200
Subject: [PATCH] dwc2/host: HFIR: Fix timing off-by-one

---
 src/portable/synopsys/dwc2/hcd_dwc2.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/portable/synopsys/dwc2/hcd_dwc2.c b/src/portable/synopsys/dwc2/hcd_dwc2.c
index 7cbef05b7..6f7551ed7 100644
--- a/src/portable/synopsys/dwc2/hcd_dwc2.c
+++ b/src/portable/synopsys/dwc2/hcd_dwc2.c
@@ -1242,9 +1242,9 @@ static void port0_enable(dwc2_regs_t* dwc2, tusb_speed_t speed) {
 
   uint32_t hfir = dwc2->hfir & ~HFIR_FRIVL_Msk;
   if (speed == TUSB_SPEED_HIGH) {
-    hfir |= 125*phy_clock;
+    hfir |= 125*phy_clock - 1; // The "- 1" is the correct value. The Synopsys databook was corrected in 3.30a
   } else {
-    hfir |= 1000*phy_clock;
+    hfir |= 1000*phy_clock - 1;
   }
 
   dwc2->hfir = hfir;