[U-Boot] [PATCH v2 2/4] usb: dwc3: Add helper functions to enable snooping and burst settings

[Rajesh Bhagat]

> -----Original Message-----
> From: Marek Vasut [mailto:marex at denx.de]
> Sent: Monday, June 06, 2016 6:24 PM
> To: Rajat Srivastava <rajat.srivastava at nxp.com>; u-boot at lists.denx.de
> Cc: l.majewski at samsung.com; sjg at chromium.org; albert.u.boot at aribaud.net;
> prabhakar at freescale.com; york sun <york.sun at nxp.com>; Mingkai Hu
> <mingkai.hu at nxp.com>; Rajesh Bhagat <rajesh.bhagat at nxp.com>;
> michal.simek at xilinx.com; felipe.balbi at linux.intel.com
> Subject: Re: [PATCH v2 2/4] usb: dwc3: Add helper functions to enable snooping and
> burst settings
> 
> On 06/06/2016 11:16 AM, Rajat Srivastava wrote:
> > Adds helper functions to enable snooping and outstanding burst beat
> > settings.
> >
> > Signed-off-by: Rajat Srivastava <rajat.srivastava at nxp.com>
> > Signed-off-by: Rajesh Bhagat <rajesh.bhagat at nxp.com>
> > ---
> > Changes in v2:
> >  - Removes SoC specific flags and added helper functions
> >
> >  drivers/usb/dwc3/core.c | 45
> > +++++++++++++++++++++++++++++++++++++++++++++
> >  drivers/usb/dwc3/core.h |  7 +++++++
> >  2 files changed, 52 insertions(+)
> >
> > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index
> > 85cc96a..0b3c596 100644
> > --- a/drivers/usb/dwc3/core.c
> > +++ b/drivers/usb/dwc3/core.c
> > @@ -599,6 +599,51 @@ static void dwc3_core_exit_mode(struct dwc3 *dwc)
> >
> >  #define DWC3_ALIGN_MASK		(16 - 1)
> >
> > +void dwc3_core_incr_burst_enable(int index, int btype_incr_val,
> > +				 int breq_limit)
> > +{
> > +	struct dwc3 *dwc;
> > +	u32 reg;
> > +
> > +	list_for_each_entry(dwc, &dwc3_list, list) {
> 

Hello Marek, 

> Why is this iterating over a list of all controllers ?

This function has to be called from Soc specific code to pass some register settings. And dwc pointer 
would not be available there. Hence, index is passed to determine dwc pointer. 

> Should this be enabled on per-controller basis by some DT prop ?
>

We are using dwc3 driver with non DT support. 

Best Regards,
Rajesh Bhagat 

 
> > +		if (dwc->index != index)
> > +			continue;
> > +
> > +		/*
> > +		 * Change burst beat and outstanding pipelined
> > +		 * transfers requests
> > +		 */
> > +		reg = dwc3_readl(dwc->regs, DWC3_GSBUSCFG0);
> > +		reg = (reg & ~DWC3_INCR_BTYPE_MASK) | btype_incr_val;
> > +		dwc3_writel(dwc->regs, DWC3_GSBUSCFG0, reg);
> > +
> > +		reg = dwc3_readl(dwc->regs, DWC3_GSBUSCFG1);
> > +		reg = (reg & ~DWC3_BREQ_LIMIT_MASK) | (breq_limit << 8);
> > +		dwc3_writel(dwc->regs, DWC3_GSBUSCFG1, reg);
> > +		break;
> > +	}
> > +}
> > +
> > +void dwc3_core_set_snooping(int index, bool snoop) {
> > +	struct dwc3 *dwc;
> > +	u32 reg;
> > +
> > +	list_for_each_entry(dwc, &dwc3_list, list) {
> > +		if (dwc->index != index)
> > +			continue;
> > +
> > +		/* Enable/Disable snooping */
> > +		reg = dwc3_readl(dwc->regs, DWC3_GSBUSCFG0);
> > +		if (snoop)
> > +			reg = reg | DWC3_SNOOP_ENABLE;
> > +		else
> > +			reg = reg & ~DWC3_SNOOP_ENABLE;
> > +		dwc3_writel(dwc->regs, DWC3_GSBUSCFG0, reg);
> > +		break;
> > +	}
> > +}
> > +
> >  /**
> >   * dwc3_uboot_init - dwc3 core uboot initialization code
> >   * @dwc3_dev: struct dwc3_device containing initialization data diff
> > --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index
> > 72d2fcd..455e7fa 100644
> > --- a/drivers/usb/dwc3/core.h
> > +++ b/drivers/usb/dwc3/core.h
> > @@ -593,6 +593,13 @@ struct dwc3_hwparams {
> >  /* HWPARAMS7 */
> >  #define DWC3_RAM1_DEPTH(n)	((n) & 0xffff)
> >
> > +/* GSBUSCFG0 */
> > +#define DWC3_SNOOP_ENABLE	(0x22220000)
> > +#define DWC3_INCR_BTYPE_MASK	(0xff)
> > +
> > +/* GSBUSCFG1 */
> > +#define DWC3_BREQ_LIMIT_MASK	(0xf00)
> > +
> >  struct dwc3_request {
> >  	struct usb_request	request;
> >  	struct list_head	list;
> >
> 
> 
> --
> Best regards,
> Marek Vasut