u-boot-brain/drivers/usb/host/xhci-dwc3.c
Rajesh Bhagat 5955bb9345 usb: xhci: dwc3: Adding reset delay requirement as per dwc3 databook
As per dwc3 databook, delay is required before taking the core out of reset.
This delay is required so that the PHY are stable, and then we can take core
out of reset.

Reference is taken from linux dwc3 code, file: drivers/usb/dwc3/core.c.

Signed-off-by: Sriram Dash <sriram.dash@freescale.com>
Signed-off-by: Rajesh Bhagat <rajesh.bhagat@freescale.com>
2015-12-07 00:15:00 +01:00

100 lines
2.4 KiB
C

/*
* Copyright 2015 Freescale Semiconductor, Inc.
*
* DWC3 controller driver
*
* Author: Ramneek Mehresh<ramneek.mehresh@freescale.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <linux/usb/dwc3.h>
void dwc3_set_mode(struct dwc3 *dwc3_reg, u32 mode)
{
clrsetbits_le32(&dwc3_reg->g_ctl,
DWC3_GCTL_PRTCAPDIR(DWC3_GCTL_PRTCAP_OTG),
DWC3_GCTL_PRTCAPDIR(mode));
}
void dwc3_phy_reset(struct dwc3 *dwc3_reg)
{
/* Assert USB3 PHY reset */
setbits_le32(&dwc3_reg->g_usb3pipectl[0], DWC3_GUSB3PIPECTL_PHYSOFTRST);
/* Assert USB2 PHY reset */
setbits_le32(&dwc3_reg->g_usb2phycfg, DWC3_GUSB2PHYCFG_PHYSOFTRST);
mdelay(100);
/* Clear USB3 PHY reset */
clrbits_le32(&dwc3_reg->g_usb3pipectl[0], DWC3_GUSB3PIPECTL_PHYSOFTRST);
/* Clear USB2 PHY reset */
clrbits_le32(&dwc3_reg->g_usb2phycfg, DWC3_GUSB2PHYCFG_PHYSOFTRST);
}
void dwc3_core_soft_reset(struct dwc3 *dwc3_reg)
{
/* Before Resetting PHY, put Core in Reset */
setbits_le32(&dwc3_reg->g_ctl, DWC3_GCTL_CORESOFTRESET);
/* reset USB3 phy - if required */
dwc3_phy_reset(dwc3_reg);
mdelay(100);
/* After PHYs are stable we can take Core out of reset state */
clrbits_le32(&dwc3_reg->g_ctl, DWC3_GCTL_CORESOFTRESET);
}
int dwc3_core_init(struct dwc3 *dwc3_reg)
{
u32 reg;
u32 revision;
unsigned int dwc3_hwparams1;
revision = readl(&dwc3_reg->g_snpsid);
/* This should read as U3 followed by revision number */
if ((revision & DWC3_GSNPSID_MASK) != 0x55330000) {
puts("this is not a DesignWare USB3 DRD Core\n");
return -1;
}
dwc3_core_soft_reset(dwc3_reg);
dwc3_hwparams1 = readl(&dwc3_reg->g_hwparams1);
reg = readl(&dwc3_reg->g_ctl);
reg &= ~DWC3_GCTL_SCALEDOWN_MASK;
reg &= ~DWC3_GCTL_DISSCRAMBLE;
switch (DWC3_GHWPARAMS1_EN_PWROPT(dwc3_hwparams1)) {
case DWC3_GHWPARAMS1_EN_PWROPT_CLK:
reg &= ~DWC3_GCTL_DSBLCLKGTNG;
break;
default:
debug("No power optimization available\n");
}
/*
* WORKAROUND: DWC3 revisions <1.90a have a bug
* where the device can fail to connect at SuperSpeed
* and falls back to high-speed mode which causes
* the device to enter a Connect/Disconnect loop
*/
if ((revision & DWC3_REVISION_MASK) < 0x190a)
reg |= DWC3_GCTL_U2RSTECN;
writel(reg, &dwc3_reg->g_ctl);
return 0;
}
void dwc3_set_fladj(struct dwc3 *dwc3_reg, u32 val)
{
setbits_le32(&dwc3_reg->g_fladj, GFLADJ_30MHZ_REG_SEL |
GFLADJ_30MHZ(val));
}