From a610d35cc8780e781321ea8d002d5fef8484bf59 Mon Sep 17 00:00:00 2001 From: Oliver O'Halloran Date: Wed, 22 Jul 2020 16:57:08 +1000 Subject: [PATCH] powerpc/powernv/sriov: Factor out M64 BAR setup The sequence required to use the single PE BAR mode is kinda janky and requires a little explanation. The API was designed with P7-IOC style windows where the setup process is something like: 1. Configure the window start / end address 2. Enable the window 3. Map the segments of each window to the PE For Single PE BARs the process is: 1. Set the PE for segment zero on a disabled window 2. Set the range 3. Enable the window Move the OPAL calls into their own helper functions where the quirks can be contained. Signed-off-by: Oliver O'Halloran Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200722065715.1432738-9-oohall@gmail.com --- arch/powerpc/platforms/powernv/pci-sriov.c | 129 ++++++++++++++++++++++------- 1 file changed, 100 insertions(+), 29 deletions(-) diff --git a/arch/powerpc/platforms/powernv/pci-sriov.c b/arch/powerpc/platforms/powernv/pci-sriov.c index 261df23..5d2f5d5 100644 --- a/arch/powerpc/platforms/powernv/pci-sriov.c +++ b/arch/powerpc/platforms/powernv/pci-sriov.c @@ -319,6 +319,99 @@ static int pnv_pci_vf_release_m64(struct pci_dev *pdev, u16 num_vfs) return 0; } + +/* + * PHB3 and beyond support segmented windows. The window's address range + * is subdivided into phb->ioda.total_pe_num segments and there's a 1-1 + * mapping between PEs and segments. + */ +static int64_t pnv_ioda_map_m64_segmented(struct pnv_phb *phb, + int window_id, + resource_size_t start, + resource_size_t size) +{ + int64_t rc; + + rc = opal_pci_set_phb_mem_window(phb->opal_id, + OPAL_M64_WINDOW_TYPE, + window_id, + start, + 0, /* unused */ + size); + if (rc) + goto out; + + rc = opal_pci_phb_mmio_enable(phb->opal_id, + OPAL_M64_WINDOW_TYPE, + window_id, + OPAL_ENABLE_M64_SPLIT); +out: + if (rc) + pr_err("Failed to map M64 window #%d: %lld\n", window_id, rc); + + return rc; +} + +static int64_t pnv_ioda_map_m64_single(struct pnv_phb *phb, + int pe_num, + int window_id, + resource_size_t start, + resource_size_t size) +{ + int64_t rc; + + /* + * The API for setting up m64 mmio windows seems to have been designed + * with P7-IOC in mind. For that chip each M64 BAR (window) had a fixed + * split of 8 equally sized segments each of which could individually + * assigned to a PE. + * + * The problem with this is that the API doesn't have any way to + * communicate the number of segments we want on a BAR. This wasn't + * a problem for p7-ioc since you didn't have a choice, but the + * single PE windows added in PHB3 don't map cleanly to this API. + * + * As a result we've got this slightly awkward process where we + * call opal_pci_map_pe_mmio_window() to put the single in single + * PE mode, and set the PE for the window before setting the address + * bounds. We need to do it this way because the single PE windows + * for PHB3 have different alignment requirements on PHB3. + */ + rc = opal_pci_map_pe_mmio_window(phb->opal_id, + pe_num, + OPAL_M64_WINDOW_TYPE, + window_id, + 0); + if (rc) + goto out; + + /* + * NB: In single PE mode the window needs to be aligned to 32MB + */ + rc = opal_pci_set_phb_mem_window(phb->opal_id, + OPAL_M64_WINDOW_TYPE, + window_id, + start, + 0, /* ignored by FW, m64 is 1-1 */ + size); + if (rc) + goto out; + + /* + * Now actually enable it. We specified the BAR should be in "non-split" + * mode so FW will validate that the BAR is in single PE mode. + */ + rc = opal_pci_phb_mmio_enable(phb->opal_id, + OPAL_M64_WINDOW_TYPE, + window_id, + OPAL_ENABLE_M64_NON_SPLIT); +out: + if (rc) + pr_err("Error mapping single PE BAR\n"); + + return rc; +} + static int pnv_pci_vf_assign_m64(struct pci_dev *pdev, u16 num_vfs) { struct pnv_iov_data *iov; @@ -329,7 +422,6 @@ static int pnv_pci_vf_assign_m64(struct pci_dev *pdev, u16 num_vfs) int64_t rc; int total_vfs; resource_size_t size, start; - int pe_num; int m64_bars; phb = pci_bus_to_pnvhb(pdev->bus); @@ -358,49 +450,28 @@ static int pnv_pci_vf_assign_m64(struct pci_dev *pdev, u16 num_vfs) } while (test_and_set_bit(win, &phb->ioda.m64_bar_alloc)); set_bit(win, iov->used_m64_bar_mask); + if (iov->m64_single_mode) { size = pci_iov_resource_size(pdev, PCI_IOV_RESOURCES + i); start = res->start + size * j; + rc = pnv_ioda_map_m64_single(phb, win, + iov->pe_num_map[j], + start, + size); } else { size = resource_size(res); start = res->start; - } - /* Map the M64 here */ - if (iov->m64_single_mode) { - pe_num = iov->pe_num_map[j]; - rc = opal_pci_map_pe_mmio_window(phb->opal_id, - pe_num, OPAL_M64_WINDOW_TYPE, - win, 0); + rc = pnv_ioda_map_m64_segmented(phb, win, start, + size); } - rc = opal_pci_set_phb_mem_window(phb->opal_id, - OPAL_M64_WINDOW_TYPE, - win, - start, - 0, /* unused */ - size); - - if (rc != OPAL_SUCCESS) { dev_err(&pdev->dev, "Failed to map M64 window #%d: %lld\n", win, rc); goto m64_failed; } - - if (iov->m64_single_mode) - rc = opal_pci_phb_mmio_enable(phb->opal_id, - OPAL_M64_WINDOW_TYPE, win, 2); - else - rc = opal_pci_phb_mmio_enable(phb->opal_id, - OPAL_M64_WINDOW_TYPE, win, 1); - - if (rc != OPAL_SUCCESS) { - dev_err(&pdev->dev, "Failed to enable M64 window #%d: %llx\n", - win, rc); - goto m64_failed; - } } } return 0; -- 2.7.4