Re: [PATCH v6 06/18] PCI: designware-ep: Add generic function for raising MSI irq

From: Jingoo Han
Date: Thu Dec 21 2017 - 11:47:39 EST


On Wednesday, December 20, 2017 2:33 PM, Joao Pinto wrote:
>
>
> Hi,
>
> Ãs 11:29 PM de 12/19/2017, Niklas Cassel escreveu:
> > Add a generic function for raising MSI irqs that can be used by all
> > DWC based controllers.
> >
> > Note that certain controllers, like DRA7xx, have a special convenience
> > register for raising MSI irqs that doesn't require you to explicitly map
> > the MSI address. Therefore, it is likely that certain drivers will
> > not use this generic function, even if they can.
> >
> > Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx>
> > ---
> > drivers/pci/dwc/pcie-designware-ep.c | 35
> +++++++++++++++++++++++++++++++++++
> > drivers/pci/dwc/pcie-designware.h | 9 +++++++++
> > 2 files changed, 44 insertions(+)
> >
> > diff --git a/drivers/pci/dwc/pcie-designware-ep.c
> b/drivers/pci/dwc/pcie-designware-ep.c
> > index 700ed2f4becf..c5aa1cac5041 100644
> > --- a/drivers/pci/dwc/pcie-designware-ep.c
> > +++ b/drivers/pci/dwc/pcie-designware-ep.c
> > @@ -282,6 +282,41 @@ static const struct pci_epc_ops epc_ops = {
> > .stop = dw_pcie_ep_stop,
> > };
> >
> > +int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep,
> > + u8 interrupt_num)
> > +{
> > + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > + struct pci_epc *epc = ep->epc;
> > + u16 msg_ctrl, msg_data;
> > + u32 msg_addr_lower, msg_addr_upper;
> > + u64 msg_addr;
> > + bool has_upper;
> > + int ret;
> > +
> > + /* Raise MSI per the PCI Local Bus Specification Revision 3.0,
> 6.8.1. */
> > + msg_ctrl = dw_pcie_readw_dbi(pci, MSI_MESSAGE_CONTROL);
> > + has_upper = !!(msg_ctrl & PCI_MSI_FLAGS_64BIT);
> > + msg_addr_lower = dw_pcie_readl_dbi(pci, MSI_MESSAGE_ADDR_L32);
> > + if (has_upper) {
> > + msg_addr_upper = dw_pcie_readl_dbi(pci,
> MSI_MESSAGE_ADDR_U32);
> > + msg_data = dw_pcie_readw_dbi(pci, MSI_MESSAGE_DATA_64);
> > + } else {
> > + msg_addr_upper = 0;
> > + msg_data = dw_pcie_readw_dbi(pci, MSI_MESSAGE_DATA_32);
> > + }
> > + msg_addr = ((u64) msg_addr_upper) << 32 | msg_addr_lower;
> > + ret = dw_pcie_ep_map_addr(epc, ep->msi_mem_phys, msg_addr,
> > + epc->mem->page_size);
> > + if (ret)
> > + return ret;
> > +
> > + writel(msg_data | (interrupt_num - 1), ep->msi_mem);
> > +
> > + dw_pcie_ep_unmap_addr(epc, ep->msi_mem_phys);
> > +
> > + return 0;
> > +}
> > +
> > void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
> > {
> > struct pci_epc *epc = ep->epc;
> > diff --git a/drivers/pci/dwc/pcie-designware.h b/drivers/pci/dwc/pcie-
> designware.h
> > index 37dfad8d003f..24edac035160 100644
> > --- a/drivers/pci/dwc/pcie-designware.h
> > +++ b/drivers/pci/dwc/pcie-designware.h
> > @@ -106,6 +106,8 @@
> > #define MSI_CAP_MME_MASK (7 << MSI_CAP_MME_SHIFT)
> > #define MSI_MESSAGE_ADDR_L32 0x54
> > #define MSI_MESSAGE_ADDR_U32 0x58
> > +#define MSI_MESSAGE_DATA_32 0x58
> > +#define MSI_MESSAGE_DATA_64 0x5C
> >
> > /*
> > * Maximum number of MSI IRQs can be 256 per controller. But keep
> > @@ -338,6 +340,7 @@ static inline int dw_pcie_host_init(struct pcie_port
> *pp)
> > void dw_pcie_ep_linkup(struct dw_pcie_ep *ep);
> > int dw_pcie_ep_init(struct dw_pcie_ep *ep);
> > void dw_pcie_ep_exit(struct dw_pcie_ep *ep);
> > +int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 interrupt_num);
> > void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar);
> > #else
> > static inline void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
> > @@ -353,6 +356,12 @@ static inline void dw_pcie_ep_exit(struct
> dw_pcie_ep *ep)
> > {
> > }
> >
> > +static inline int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep,
> > + u8 interrupt_num)
> > +{
> > + return 0;
> > +}
> > +
> > static inline void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum
> pci_barno bar)
> > {
> > }
> >
>
> Acked-by: Joao Pinto <jpinto@xxxxxxxxxxxx>

Acked-by: Jingoo Han <jingoohan1@xxxxxxxxx>

Best regards,
Jingoo Han