| Message ID | 20241114-ep-msi-v7-3-d4ac7aafbd2c@nxp.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: EP: Add RC-to-EP doorbell with platform MSI controller | expand |
On Thu, Nov 14, 2024 at 05:52:39PM -0500, Frank Li wrote: > Introduce the helper function pci_epf_align_addr() to adjust addresses > according to PCI BAR alignment requirements, converting addresses into base > and offset values. > > Signed-off-by: Frank Li <Frank.Li@nxp.com> > --- > change from v6 to v7 > - new patch > --- > drivers/pci/endpoint/pci-epf-core.c | 39 +++++++++++++++++++++++++++++++++++++ > include/linux/pci-epf.h | 13 +++++++++++++ > 2 files changed, 52 insertions(+) > > diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c > index 8fa2797d4169a..a3f172cc786e9 100644 > --- a/drivers/pci/endpoint/pci-epf-core.c > +++ b/drivers/pci/endpoint/pci-epf-core.c > @@ -464,6 +464,45 @@ struct pci_epf *pci_epf_create(const char *name) > } > EXPORT_SYMBOL_GPL(pci_epf_create); > > +/** > + * pci_epf_align_addr() - Get base address and offset that match bar's > + * alignment requirement > + * @epf: the EPF device > + * @addr: the address of the memory > + * @bar: the BAR number corresponding to map addr > + * @base: return base address, which match BAR's alignment requirement, nothing > + * return if NULL > + * @off: return offset, nothing return if NULL > + * > + * Helper function to convert input 'addr' to base and offset, which match > + * BAR's alignment requirement. > + */ > +int pci_epf_align_addr(struct pci_epf *epf, enum pci_barno bar, u64 addr, u64 *base, size_t *off) Nit: perhaps rename this function to: pci_epf_align_ib_addr() or pci_epf_align_inbound_addr() to more clearly not confuse this with: if (epc->ops->align_addr) .align_addr() (Ideally those functions should have been named align_ob_addr(), or align_outbound_addr()) > +{ > + const struct pci_epc_features *epc_features; > + u64 align; > + > + epc_features = pci_epc_get_features(epf->epc, epf->func_no, epf->vfunc_no); > + if (!epc_features) { > + dev_err(&epf->dev, "epc_features not implemented\n"); > + return -EOPNOTSUPP; > + } > + > + align = epc_features->align; > + align = align ? align : 128; > + if (epc_features->bar[bar].type == BAR_FIXED) > + align = max(epc_features->bar[bar].fixed_size, align); > + > + if (base) > + *base = round_down(addr, align); > + > + if (off) > + *off = addr & (align - 1); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(pci_epf_align_addr); > + > static void pci_epf_dev_release(struct device *dev) > { > struct pci_epf *epf = to_pci_epf(dev); > diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h > index 5374e6515ffa0..20f4f31ba9b36 100644 > --- a/include/linux/pci-epf.h > +++ b/include/linux/pci-epf.h > @@ -238,6 +238,19 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar, > enum pci_epc_interface_type type); > void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar, > enum pci_epc_interface_type type); > + > +int pci_epf_align_addr(struct pci_epf *epf, enum pci_barno bar, u64 addr, u64 *base, size_t *off); > +static inline int pci_epf_align_addr_lo_hi(struct pci_epf *epf, enum pci_barno bar, > + u32 low, u32 high, u64 *base, size_t *off) > +{ > + u64 addr = high; > + > + addr <<= 32; > + addr |= low; > + > + return pci_epf_align_addr(epf, bar, addr, base, off); > +} I'm not sure if this function deserves to live :) Can't the caller just do this before calling pci_epf_align_addr() ? Kind regards, Niklas
On Thu, Nov 14, 2024 at 05:52:39PM -0500, Frank Li wrote: > Introduce the helper function pci_epf_align_addr() to adjust addresses > according to PCI BAR alignment requirements, converting addresses into base > and offset values. > > Signed-off-by: Frank Li <Frank.Li@nxp.com> > --- > change from v6 to v7 > - new patch > --- > drivers/pci/endpoint/pci-epf-core.c | 39 +++++++++++++++++++++++++++++++++++++ > include/linux/pci-epf.h | 13 +++++++++++++ > 2 files changed, 52 insertions(+) > > diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c > index 8fa2797d4169a..a3f172cc786e9 100644 > --- a/drivers/pci/endpoint/pci-epf-core.c > +++ b/drivers/pci/endpoint/pci-epf-core.c > @@ -464,6 +464,45 @@ struct pci_epf *pci_epf_create(const char *name) > } > EXPORT_SYMBOL_GPL(pci_epf_create); > > +/** > + * pci_epf_align_addr() - Get base address and offset that match bar's > + * alignment requirement > + * @epf: the EPF device > + * @addr: the address of the memory > + * @bar: the BAR number corresponding to map addr > + * @base: return base address, which match BAR's alignment requirement, nothing > + * return if NULL > + * @off: return offset, nothing return if NULL > + * > + * Helper function to convert input 'addr' to base and offset, which match > + * BAR's alignment requirement. Should we perhaps also mention that this function is not needed in the "normal case" ? (i.e. pci_epf_alloc_space() + pci_epc_set_bar()) Kind regards, Niklas
On Fri, Nov 15, 2024 at 10:53:07AM +0100, Niklas Cassel wrote: > On Thu, Nov 14, 2024 at 05:52:39PM -0500, Frank Li wrote: > > Introduce the helper function pci_epf_align_addr() to adjust addresses > > according to PCI BAR alignment requirements, converting addresses into base > > and offset values. > > > > Signed-off-by: Frank Li <Frank.Li@nxp.com> > > --- > > change from v6 to v7 > > - new patch > > --- > > drivers/pci/endpoint/pci-epf-core.c | 39 +++++++++++++++++++++++++++++++++++++ > > include/linux/pci-epf.h | 13 +++++++++++++ > > 2 files changed, 52 insertions(+) > > > > diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c > > index 8fa2797d4169a..a3f172cc786e9 100644 > > --- a/drivers/pci/endpoint/pci-epf-core.c > > +++ b/drivers/pci/endpoint/pci-epf-core.c > > @@ -464,6 +464,45 @@ struct pci_epf *pci_epf_create(const char *name) > > } > > EXPORT_SYMBOL_GPL(pci_epf_create); > > > > +/** > > + * pci_epf_align_addr() - Get base address and offset that match bar's > > + * alignment requirement > > + * @epf: the EPF device > > + * @addr: the address of the memory > > + * @bar: the BAR number corresponding to map addr > > + * @base: return base address, which match BAR's alignment requirement, nothing > > + * return if NULL > > + * @off: return offset, nothing return if NULL > > + * > > + * Helper function to convert input 'addr' to base and offset, which match > > + * BAR's alignment requirement. > > + */ > > +int pci_epf_align_addr(struct pci_epf *epf, enum pci_barno bar, u64 addr, u64 *base, size_t *off) > > Nit: perhaps rename this function to: > pci_epf_align_ib_addr() > or > pci_epf_align_inbound_addr() > > to more clearly not confuse this with: > if (epc->ops->align_addr) > .align_addr() > (Ideally those functions should have been named align_ob_addr(), > or align_outbound_addr()) > > > > +{ > > + const struct pci_epc_features *epc_features; > > + u64 align; > > + > > + epc_features = pci_epc_get_features(epf->epc, epf->func_no, epf->vfunc_no); > > + if (!epc_features) { > > + dev_err(&epf->dev, "epc_features not implemented\n"); > > + return -EOPNOTSUPP; > > + } > > + > > + align = epc_features->align; > > + align = align ? align : 128; > > + if (epc_features->bar[bar].type == BAR_FIXED) > > + align = max(epc_features->bar[bar].fixed_size, align); > > + > > + if (base) > > + *base = round_down(addr, align); > > + > > + if (off) > > + *off = addr & (align - 1); > > + > > + return 0; > > +} > > +EXPORT_SYMBOL_GPL(pci_epf_align_addr); > > + > > static void pci_epf_dev_release(struct device *dev) > > { > > struct pci_epf *epf = to_pci_epf(dev); > > diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h > > index 5374e6515ffa0..20f4f31ba9b36 100644 > > --- a/include/linux/pci-epf.h > > +++ b/include/linux/pci-epf.h > > @@ -238,6 +238,19 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar, > > enum pci_epc_interface_type type); > > void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar, > > enum pci_epc_interface_type type); > > + > > +int pci_epf_align_addr(struct pci_epf *epf, enum pci_barno bar, u64 addr, u64 *base, size_t *off); > > +static inline int pci_epf_align_addr_lo_hi(struct pci_epf *epf, enum pci_barno bar, > > + u32 low, u32 high, u64 *base, size_t *off) > > +{ > > + u64 addr = high; > > + > > + addr <<= 32; > > + addr |= low; > > + > > + return pci_epf_align_addr(epf, bar, addr, base, off); > > +} > > I'm not sure if this function deserves to live :) > Can't the caller just do this before calling pci_epf_align_addr() ? Ideally, kernel should have macro to combine 32bit macro to a 64bit, but I have not found it. It is quite easy to make error or warning by simple (high << 32 | low) It needs ((u64) high << 32 | low) at least. I just want to avoid everyone to struggle simple issue. And msi_msg use lo and hi. pci_function_test actually just demostrate how to use doorbell. if other function driver use doorbell in future, avoid "(u64) high << 32 | low" copy to everywhere. Maybe like upper_32_bits(), add global helper macro #define low32_high32_to_64bit(l, h) ((u64)(h) << 32 | low) Frank > > > Kind regards, > Niklas
On Fri, Nov 15, 2024 at 11:43:22AM -0500, Frank Li wrote: > On Fri, Nov 15, 2024 at 10:53:07AM +0100, Niklas Cassel wrote: > > On Thu, Nov 14, 2024 at 05:52:39PM -0500, Frank Li wrote: > > > +static inline int pci_epf_align_addr_lo_hi(struct pci_epf *epf, enum pci_barno bar, > > > + u32 low, u32 high, u64 *base, size_t *off) > > > +{ > > > + u64 addr = high; > > > + > > > + addr <<= 32; > > > + addr |= low; > > > + > > > + return pci_epf_align_addr(epf, bar, addr, base, off); > > > +} > > > > I'm not sure if this function deserves to live :) > > Can't the caller just do this before calling pci_epf_align_addr() ? > > Ideally, kernel should have macro to combine 32bit macro to a 64bit, but > I have not found it. > > It is quite easy to make error or warning by simple > (high << 32 | low) > > It needs ((u64) high << 32 | low) at least. I just want to avoid everyone > to struggle simple issue. > > And msi_msg use lo and hi. pci_function_test actually just demostrate how > to use doorbell. if other function driver use doorbell in future, avoid > "(u64) high << 32 | low" copy to everywhere. Keeping the helper is fine with me, but it probably should be renamed to include _ib_ or _inbound_ in the function name, similar to the comment for pci_epf_align_addr(). Kind regards, Niklas
diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c index 8fa2797d4169a..a3f172cc786e9 100644 --- a/drivers/pci/endpoint/pci-epf-core.c +++ b/drivers/pci/endpoint/pci-epf-core.c @@ -464,6 +464,45 @@ struct pci_epf *pci_epf_create(const char *name) } EXPORT_SYMBOL_GPL(pci_epf_create); +/** + * pci_epf_align_addr() - Get base address and offset that match bar's + * alignment requirement + * @epf: the EPF device + * @addr: the address of the memory + * @bar: the BAR number corresponding to map addr + * @base: return base address, which match BAR's alignment requirement, nothing + * return if NULL + * @off: return offset, nothing return if NULL + * + * Helper function to convert input 'addr' to base and offset, which match + * BAR's alignment requirement. + */ +int pci_epf_align_addr(struct pci_epf *epf, enum pci_barno bar, u64 addr, u64 *base, size_t *off) +{ + const struct pci_epc_features *epc_features; + u64 align; + + epc_features = pci_epc_get_features(epf->epc, epf->func_no, epf->vfunc_no); + if (!epc_features) { + dev_err(&epf->dev, "epc_features not implemented\n"); + return -EOPNOTSUPP; + } + + align = epc_features->align; + align = align ? align : 128; + if (epc_features->bar[bar].type == BAR_FIXED) + align = max(epc_features->bar[bar].fixed_size, align); + + if (base) + *base = round_down(addr, align); + + if (off) + *off = addr & (align - 1); + + return 0; +} +EXPORT_SYMBOL_GPL(pci_epf_align_addr); + static void pci_epf_dev_release(struct device *dev) { struct pci_epf *epf = to_pci_epf(dev); diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index 5374e6515ffa0..20f4f31ba9b36 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -238,6 +238,19 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar, enum pci_epc_interface_type type); void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar, enum pci_epc_interface_type type); + +int pci_epf_align_addr(struct pci_epf *epf, enum pci_barno bar, u64 addr, u64 *base, size_t *off); +static inline int pci_epf_align_addr_lo_hi(struct pci_epf *epf, enum pci_barno bar, + u32 low, u32 high, u64 *base, size_t *off) +{ + u64 addr = high; + + addr <<= 32; + addr |= low; + + return pci_epf_align_addr(epf, bar, addr, base, off); +} + int pci_epf_bind(struct pci_epf *epf); void pci_epf_unbind(struct pci_epf *epf); int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf);
Introduce the helper function pci_epf_align_addr() to adjust addresses according to PCI BAR alignment requirements, converting addresses into base and offset values. Signed-off-by: Frank Li <Frank.Li@nxp.com> --- change from v6 to v7 - new patch --- drivers/pci/endpoint/pci-epf-core.c | 39 +++++++++++++++++++++++++++++++++++++ include/linux/pci-epf.h | 13 +++++++++++++ 2 files changed, 52 insertions(+)