On 2022-09-23 at 05:17:43 -0700, matthew.gerlach@xxxxxxxxxxxxxxx wrote: > From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx> > > Define and use a DFHv1 parameter to add generic support for MSIX > interrupts for DFL devices. > > Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx> > --- > v2: fix kernel doc > clarify use of DFH_VERSION field > --- > drivers/fpga/dfl.c | 60 +++++++++++++++++++++++++++++++++++++++++---- > include/linux/dfl.h | 14 +++++++++++ > 2 files changed, 69 insertions(+), 5 deletions(-) > > diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c > index 1132f3c10440..dfd3f563c92d 100644 > --- a/drivers/fpga/dfl.c > +++ b/drivers/fpga/dfl.c > @@ -941,23 +941,22 @@ static int parse_feature_irqs(struct build_feature_devs_info *binfo, > void __iomem *base = binfo->ioaddr + ofst; > unsigned int i, ibase, inr = 0; > enum dfl_id_type type; > - int virq; > + int virq, off; > u64 v; > > type = feature_dev_id_type(binfo->feature_dev); > > /* > * Ideally DFL framework should only read info from DFL header, but > - * current version DFL only provides mmio resources information for > + * current version, DFHv0, only provides mmio resources information for With this patchset, it's not 'current version' anymore. > * each feature in DFL Header, no field for interrupt resources. > * Interrupt resource information is provided by specific mmio > * registers of each private feature which supports interrupt. So in > * order to parse and assign irq resources, DFL framework has to look > * into specific capability registers of these private features. > * > - * Once future DFL version supports generic interrupt resource > - * information in common DFL headers, the generic interrupt parsing > - * code will be added. But in order to be compatible to old version > + * DFHv1 supports generic interrupt resource information in DFHv1 > + * parameter blocks. But in order to be compatible to old version > * DFL, the driver may still fall back to these quirks. > */ > if (type == PORT_ID) { > @@ -981,6 +980,36 @@ static int parse_feature_irqs(struct build_feature_devs_info *binfo, > } > } > > + if (fid != FEATURE_ID_AFU && fid != PORT_FEATURE_ID_ERROR && > + fid != PORT_FEATURE_ID_UINT && fid != FME_FEATURE_ID_GLOBAL_ERR) { > + > + v = FIELD_GET(DFH_VERSION, readq(base)); > + switch (v) { > + case 0: > + break; In last version, you mentioned that there will be no quirk for DFLv1, so how about: v = FIELD_GET(DFH_VERSION, readq(base)); if (v == 0) { /* quirks */ } else { /* parse PARAM MSIX */ } No need to check specific feature ids again. Thanks, Yilun > + > + case 1: > + v = readq(base + DFHv1_CSR_SIZE_GRP); > + if (FIELD_GET(DFHv1_CSR_SIZE_GRP_HAS_PARAMS, v)) { > + off = dfl_find_param(base + DFHv1_PARAM_HDR, ofst, > + DFHv1_PARAM_ID_MSIX); > + if (off >= 0) { > + ibase = readl(base + DFHv1_PARAM_HDR + > + off + DFHv1_PARAM_MSIX_STARTV); > + inr = readl(base + DFHv1_PARAM_HDR + > + off + DFHv1_PARAM_MSIX_NUMV); > + dev_dbg(binfo->dev, "start %d num %d fid 0x%x\n", > + ibase, inr, fid); > + } > + } > + break; > + > + default: > + dev_warn(binfo->dev, "unexpected DFH version %lld\n", v); > + break; > + } > + } > + > if (!inr) { > *irq_base = 0; > *nr_irqs = 0; > @@ -1879,6 +1908,27 @@ long dfl_feature_ioctl_set_irq(struct platform_device *pdev, > } > EXPORT_SYMBOL_GPL(dfl_feature_ioctl_set_irq); > > +int dfl_find_param(void __iomem *base, resource_size_t max, int param) > +{ > + int off = 0; > + u64 v, next; > + > + while (off < max) { > + v = readq(base + off); > + if (param == FIELD_GET(DFHv1_PARAM_HDR_ID, v)) > + return off; > + > + next = FIELD_GET(DFHv1_PARAM_HDR_NEXT_OFFSET, v); > + if (!next) > + break; > + > + off += next; > + } > + > + return -ENOENT; > +} > +EXPORT_SYMBOL_GPL(dfl_find_param); > + > static void __exit dfl_fpga_exit(void) > { > dfl_chardev_uinit(); > diff --git a/include/linux/dfl.h b/include/linux/dfl.h > index 1e53468ba8d8..33e21c360671 100644 > --- a/include/linux/dfl.h > +++ b/include/linux/dfl.h > @@ -63,6 +63,10 @@ > #define DFHv1_PARAM_HDR_VERSION GENMASK_ULL(31, 16) /* Version Param */ > #define DFHv1_PARAM_HDR_NEXT_OFFSET GENMASK_ULL(63, 32) /* Offset of next Param */ > > +#define DFHv1_PARAM_ID_MSIX 0x1 > +#define DFHv1_PARAM_MSIX_STARTV 0x8 > +#define DFHv1_PARAM_MSIX_NUMV 0xc > + > /** > * enum dfl_id_type - define the DFL FIU types > */ > @@ -136,4 +140,14 @@ void dfl_driver_unregister(struct dfl_driver *dfl_drv); > module_driver(__dfl_driver, dfl_driver_register, \ > dfl_driver_unregister) > > +/** > + * dfl_find_param() - find the offset of the given parameter > + * @base: base pointer to start of dfl parameters in DFH > + * @max: maximum offset to search > + * @param: id of dfl parameter > + * > + * Return: positive offset on success, negative error code otherwise. > + */ > +int dfl_find_param(void __iomem *base, resource_size_t max, int param); > + > #endif /* __LINUX_DFL_H */ > -- > 2.25.1 >