Re: [PATCH v5 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status

[Hans Zhang]

On 5/19/26 13:41, Aksh Garg wrote:
> On 15/05/26 20:27, Hans Zhang wrote:
> > Extend debugfs support to LGA-based Cadence PCIe controllers. The
> > 'ltssm_status' file now works for both HPA and LGA IP by selecting the
> > appropriate register access based on the 'is_hpa' flag.
> >
> > Signed-off-by: Hans Zhang <18255117159@xxxxxxx>
> > ---
> > Hi Aksh
> >
> > Could you please assist in checking whether the ltssm_status of LGA is
> > correct? If there are any inaccuracies, please point them out.
> > ---
> >   .../controller/cadence/pcie-cadence-debugfs.c | 61 ++++++++++++++++++-
> >   .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
> >   .../controller/cadence/pcie-cadence-host.c    |  9 ++-
> >   drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
> >   4 files changed, 112 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c b/ 
> > drivers/pci/controller/cadence/pcie-cadence-debugfs.c
> > index 97c5deef2b1a..ac985699b974 100644
> > --- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
> > +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
> > @@ -13,6 +13,58 @@
> >   #define CDNS_DEBUGFS_BUF_MAX        128
> > +static const char *cdns_pcie_lga_ltssm_status_string(enum 
> > cdns_pcie_lga_ltssm ltssm)
> > +{
> > +    const char *str;
> > +
> > +    switch (ltssm) {
> > +#define CDNS_PCIE_LGA_LTSSM_NAME(n) case n: str = #n; break
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_DETECT_QUIET);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_DETECT_ACTIVE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_POLLING_ACTIVE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_POLLING_COMPLIANCE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_POLLING_CONFIGURATION);
> > +    
> > CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_CONFIGURATION_LINKWIDTH_START);
> > +    
> > CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_CONFIGURATION_LINKWIDTH_ACCEPT);
> > +    
> > CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_CONFIGURATION_LANENUM_ACCEPT);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_CONFIGURATION_LANENUM_WAIT);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_CONFIGURATION_COMPLETE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_CONFIGURATION_IDLE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_RCVRLOCK);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_SPEED);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_RCVRCFG);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_IDLE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_L0);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RX_L0S_ENTRY);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RX_L0S_IDLE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RX_L0S_FTS);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_TX_L0S_ENTRY);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_TX_L0S_IDLE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_TX_L0S_FTS);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_L1_ENTRY);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_L1_IDLE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_L2_IDLE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_L2_TRANSMITWAKE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_DISABLED);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LOOPBACK_ENTRY_MASTER);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LOOPBACK_ACTIVE_MASTER);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LOOPBACK_EXIT_MASTER);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LOOPBACK_ENTRY_SLAVE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LOOPBACK_ACTIVE_SLAVE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LOOPBACK_EXIT_SLAVE);
> > +    CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_HOT_RESET);
> > +    
> > CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_EQUALIZATION_PHASE_0);
> > +    
> > CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_EQUALIZATION_PHASE_1);
> > +    
> > CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_EQUALIZATION_PHASE_2);
> > +    
> > CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_RECOVERY_EQUALIZATION_PHASE_3);
>
> Hi Hans,
>
> You might need to rename the states as CDNS_PCIE_LGA_LTSSM_* as
> suggested by Sashiko to print the state names correctly, and also to
> complement the naming used for HPA LTSSM states.
>
> > +    default:
> > +        str = "CDNS_PCIE_LGA_LTSSM_UNKNOWN";
> > +        break;
> > +    }
> > +
> > +    return str + strlen("CDNS_PCIE_LGA_LTSSM_");
>
> I have tested for LGA IP by updating this to strlen("CDNS_PCIE_LGA_").
> The state encodings looks good to me.

Hi Aksh,

Due to the issue of copying the LTSSM code from HPA, the "LTSSM_" part 
was omitted. The next version will fix this. Thank you for your test.

eg.
s/CDNS_PCIE_LGA_L0/CDNS_PCIE_LGA_LTSSM_L0/


Best regards,
Hans


> Regards,
> Aksh Garg