Messages in this thread | | | Subject | Re: [PATCH v4 4/5] PCI: iproc: Add iProc PCIe MSI support | From | Ray Jui <> | Date | Wed, 2 Dec 2015 09:19:37 -0800 |
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On 12/2/2015 6:30 AM, Hauke Mehrtens wrote: > On 11/27/2015 06:37 PM, Ray Jui wrote: >> This patch adds PCIe MSI support for both PAXB and PAXC interfaces on >> all iProc based platforms >> >> The iProc PCIe MSI support deploys an event queue based implementation. >> Each event queue is serviced by a GIC interrupt and can support up to 64 >> MSI vectors. Host memory is allocated for the event queues, and each event >> queue consists of 64 word-sized entries. MSI data is written to the >> lower 16-bit of each entry, whereas the upper 16-bit of the entry is >> reserved for the controller for internal processing >> >> Each event queue is tracked by a head pointer and tail pointer. Head >> pointer indicates the next entry in the event queue to be processed by >> the driver and is updated by the driver after processing is done. >> The controller uses the tail pointer as the next MSI data insertion >> point. The controller ensures MSI data is flushed to host memory before >> updating the tail pointer and then triggering the interrupt >> >> MSI IRQ affinity is supported by evenly distributing the interrupts to >> each CPU core. MSI vector is moved from one GIC interrupt to another in >> order to steer to the target CPU >> >> Therefore, the actual number of supported MSI vectors is: >> >> M * 64 / N >> >> where M denotes the number of GIC interrupts (event queues), and N >> denotes the number of CPU cores >> >> This iProc event queue based MSI support should not be used with newer >> platforms with integrated MSI support in the GIC (e.g., giv2m or >> gicv3-its) >> >> Signed-off-by: Ray Jui <rjui@broadcom.com> >> Reviewed-by: Anup Patel <anup.patel@broadcom.com> >> Reviewed-by: Vikram Prakash <vikramp@broadcom.com> >> Reviewed-by: Scott Branden <sbranden@broadcom.com> >> --- >> drivers/pci/host/Kconfig | 9 + >> drivers/pci/host/Makefile | 1 + >> drivers/pci/host/pcie-iproc-bcma.c | 1 + >> drivers/pci/host/pcie-iproc-msi.c | 675 +++++++++++++++++++++++++++++++++ >> drivers/pci/host/pcie-iproc-platform.c | 1 + >> drivers/pci/host/pcie-iproc.c | 26 ++ >> drivers/pci/host/pcie-iproc.h | 23 +- >> 7 files changed, 734 insertions(+), 2 deletions(-) >> create mode 100644 drivers/pci/host/pcie-iproc-msi.c >> > > ..... >> >> int iproc_pcie_setup(struct iproc_pcie *pcie, struct list_head *res); >> int iproc_pcie_remove(struct iproc_pcie *pcie); >> >> +#ifdef CONFIG_PCI_MSI >> +int iproc_msi_init(struct iproc_pcie *pcie, struct device_node *node); >> +void iproc_msi_exit(struct iproc_pcie *pcie); >> +#else >> +static inline int iproc_msi_init(struct iproc_pcie *pcie, >> + struct device_node *node) >> +{ >> + return -ENODEV; >> +} >> +static void iproc_msi_exit(struct iproc_pcie *pcie) > > Please use static inline here. >
Right. Will fix. Thanks!
>> +{ >> +} >> +#endif >> + >> #endif /* _PCIE_IPROC_H */ >> > > Hauke >
Ray
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