STM32MP15 ahbcfg register default value sets Burst length/type (HBSTLEN)
to Single (32-bit accesses on AHB), which is not recommended, according
to STM32MP157 Reference manual [1].
This patch sets Burst length/type (HBSTLEN) so that bus transactions
target 16x32 bit accesses. This improves OTG controller performance.

[1] https://www.st.com/resource/en/reference_manual/dm00327659.pdf, p.3149

Signed-off-by: Amelie Delaunay <amelie.delau...@foss.st.com>
Acked-by: Minas Harutyunyan <minas.harutyun...@synopsys.com>
---
 drivers/usb/dwc2/params.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
index 267543c3dc38..0df693319f0a 100644
--- a/drivers/usb/dwc2/params.c
+++ b/drivers/usb/dwc2/params.c
@@ -177,6 +177,7 @@ static void dwc2_set_stm32mp15_fsotg_params(struct 
dwc2_hsotg *hsotg)
        p->i2c_enable = false;
        p->activate_stm_fs_transceiver = true;
        p->activate_stm_id_vb_detection = true;
+       p->ahbcfg = GAHBCFG_HBSTLEN_INCR16 << GAHBCFG_HBSTLEN_SHIFT;
        p->power_down = DWC2_POWER_DOWN_PARAM_NONE;
 }
 
@@ -189,6 +190,7 @@ static void dwc2_set_stm32mp15_hsotg_params(struct 
dwc2_hsotg *hsotg)
        p->host_rx_fifo_size = 440;
        p->host_nperio_tx_fifo_size = 256;
        p->host_perio_tx_fifo_size = 256;
+       p->ahbcfg = GAHBCFG_HBSTLEN_INCR16 << GAHBCFG_HBSTLEN_SHIFT;
        p->power_down = DWC2_POWER_DOWN_PARAM_NONE;
 }
 
-- 
2.17.1

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