[U-Boot] [PATCH v2] T2080QDS/PCIe: Soft Reset PCIe for down-training issue

[qiang.zhao at freescale.com]

> -----Original Message-----
> From: Kushwaha Prabhakar-B32579
> Sent: Wednesday, March 11, 2015 8:12 PM
> To: Zhao Qiang-B45475; u-boot at lists.denx.de; Sun York-R58495
> Cc: Zhao Qiang-B45475
> Subject: RE: [U-Boot] [PATCH v2] T2080QDS/PCIe: Soft Reset PCIe for down-
> training issue
> 
> Hi Zhao,
> 
> 
> > -----Original Message-----
> > From: U-Boot [mailto:u-boot-bounces at lists.denx.de] On Behalf Of Zhao
> > Qiang
> > Sent: Wednesday, March 11, 2015 2:42 PM
> > To: u-boot at lists.denx.de; Sun York-R58495
> > Cc: Zhao Qiang-B45475
> > Subject: [U-Boot] [PATCH v2] T2080QDS/PCIe: Soft Reset PCIe for
> > down-training issue
> >
> > T2080QDS PEX1/Slot#1 will down-train from x4 to x2, Soft reset PCIe
> > can fix this issue, this is a workaround.
> >
> > Signed-off-by: Zhao Qiang <B45475 at freescale.com>
> > ---
> > changes for v2
> > 	- modify the commit message
> >
> >  drivers/pci/fsl_pci_init.c | 17 +++++++++++++++++
> > include/configs/T208xQDS.h
> > |  1 +
> >  2 files changed, 18 insertions(+)
> >
> > diff --git a/drivers/pci/fsl_pci_init.c b/drivers/pci/fsl_pci_init.c
> > index 231b075..327fa7d 100644
> > --- a/drivers/pci/fsl_pci_init.c
> > +++ b/drivers/pci/fsl_pci_init.c
> > @@ -481,6 +481,23 @@ void fsl_pci_init(struct pci_controller *hose,
> > struct fsl_pci_info *pci_info)  #endif
> >  	}
> >
> > +#ifdef CONFIG_FSL_PCIE_T2080QDS_RESET
> > +		int i;
> > +		/* assert PCIe reset */
> > +		setbits_be32(&pci->pdb_stat, 0x08000000);
> > +		(void) in_be32(&pci->pdb_stat);
> > +		udelay(1000);
> > +		/* clear PCIe reset */
> > +		clrbits_be32(&pci->pdb_stat, 0x08000000);
> > +		asm("sync;isync");
> > +		for (i = 0; i < 100 && ltssm < PCI_LTSSM_L0; i++) {
> > +			pci_hose_read_config_word(hose, dev, PCI_LTSSM,
> > +						  &ltssm);
> > +			udelay(1000);
> > +		}
> > +
> > +#endif
> > +
> >  #ifdef CONFIG_SYS_P4080_ERRATUM_PCIE_A003
> >  		if (enabled == 0) {
> >  			serdes_corenet_t *srds_regs = (void
> > *)CONFIG_SYS_FSL_CORENET_SERDES_ADDR;
> > diff --git a/include/configs/T208xQDS.h b/include/configs/T208xQDS.h
> > index
> > 395472b..851b4f9 100644
> > --- a/include/configs/T208xQDS.h
> > +++ b/include/configs/T208xQDS.h
> > @@ -558,6 +558,7 @@ unsigned long get_board_ddr_clk(void);
> >  #define CONFIG_PCIE2		/* PCIE controler 2 */
> >  #define CONFIG_PCIE3		/* PCIE controler 3 */
> >  #define CONFIG_PCIE4		/* PCIE controler 4 */
> > +#define CONFIG_FSL_PCIE_T2080QDS_RESET
> 
> do we really require this new define?
> 
> Can we not manage with CONFIG_FSL_PCIE_RESET?

I read and test the code again, I think it is necessary for a new define.

> 
> -prabhakar