Hi York, Yes, it is my mean, I am not brief enough to express, thank you correct me.
Thanks -----Original Message----- From: York Sun Sent: Tuesday, August 15, 2017 11:20 PM To: Xiaowei Bao <[email protected]>; [email protected]; Priyanka Jain <[email protected]>; Z.q. Hou <[email protected]>; M.h. Lian <[email protected]>; [email protected] Subject: Re: [PATCH] PCI: layerscape: Make the pcie link up status judgement more specific On 08/15/2017 03:03 AM, Bao Xiaowei wrote: > For some special reset times for longer pcie devices, in this case, > the pcie device may on polling compliance state, the RC considers the > pcie device is link up, but the pcie device is not link up, only the > L0 state is link up state. So add the link up status judgement mechanisms. > Xiaowei, Let me try to rephrase your commit message. Correct me if I get it wrong. I think you mean Determine PCIe link status by checking L0 state. If L0 state is detected within 100ms, link status is reported as up. > Signed-off-by: Bao Xiaowei <[email protected]> > --- For future patches, please add change log here and revision number in the subject. > drivers/pci/pcie_layerscape.c | 25 +++++++++++++++++++++---- > drivers/pci/pcie_layerscape.h | 3 +++ > 2 files changed, 24 insertions(+), 4 deletions(-) > > diff --git a/drivers/pci/pcie_layerscape.c > b/drivers/pci/pcie_layerscape.c index 78cde21..4db95c5 100644 > --- a/drivers/pci/pcie_layerscape.c > +++ b/drivers/pci/pcie_layerscape.c > @@ -69,13 +69,30 @@ static int ls_pcie_ltssm(struct ls_pcie *pcie) > > static int ls_pcie_link_up(struct ls_pcie *pcie) > { > - int ltssm; > + int ltssm, i; > > ltssm = ls_pcie_ltssm(pcie); > - if (ltssm < LTSSM_PCIE_L0) > - return 0; > > - return 1; > + /* > + * For some special reset times for longer pcie devices, > + * the pcie device may on polling compliance state, > + * on this state, if the device can restored to the L0 state > + * within 100ms considers the pcie device is link up > + */ > + if (ltssm == LTSSM_PCIE_DETECT_QUIET || > + ltssm == LTSSM_PCIE_DETECT_ACTIVE) { Please explain the above two lines with comment. > + return 0; > + } else if (ltssm == LTSSM_PCIE_L0) { > + return 1; > + } else { How about this comment? /* * For some devices requiring longer reset time, check if L0 * state can be reached within 100ms. */ > + for (i = 0; i < 100; i++) { > + udelay(1000); > + ltssm = ls_pcie_ltssm(pcie); > + if (ltssm == LTSSM_PCIE_L0) > + return 1; > + } > + return 0; > + } > } > > static void ls_pcie_cfg0_set_busdev(struct ls_pcie *pcie, u32 > busdev) diff --git a/drivers/pci/pcie_layerscape.h > b/drivers/pci/pcie_layerscape.h index 782e3ab..4313e85 100644 > --- a/drivers/pci/pcie_layerscape.h > +++ b/drivers/pci/pcie_layerscape.h > @@ -70,6 +70,9 @@ > > #define LTSSM_STATE_MASK 0x3f > #define LTSSM_PCIE_L0 0x11 /* L0 state */ > +#define LTSSM_PCIE_DETECT_QUIET 0x00 /* L0 state */ > +#define LTSSM_PCIE_DETECT_ACTIVE 0x01 /* L0 state */ > +#define LTSSM_PCIE_L0 0x11 /* L0 state */ > > #define PCIE_DBI_SIZE 0x100000 /* 1M */ > > York _______________________________________________ U-Boot mailing list [email protected] https://lists.denx.de/listinfo/u-boot
