From 793908d60b8745c386b9f4e29eb702f74ceb0886 Mon Sep 17 00:00:00 2001 From: Jerome Brunet Date: Thu, 24 Apr 2025 10:34:04 +0200 Subject: [PATCH 1/8] PCI: endpoint: Retain fixed-size BAR size as well as aligned size When allocating space for an endpoint function on a BAR with a fixed size, the size saved in 'struct pci_epf_bar.size' should be the fixed size as expected by pci_epc_set_bar(). However, if pci_epf_alloc_space() increased the allocation size to accommodate iATU alignment requirements, it previously saved the larger aligned size in .size, which broke pci_epc_set_bar(). To solve this, keep the fixed BAR size in .size and save the aligned size in a new .aligned_size for use when deallocating it. Fixes: 2a9a801620ef ("PCI: endpoint: Add support to specify alignment for buffers allocated to BARs") Signed-off-by: Jerome Brunet [mani: commit message fixup] Signed-off-by: Manivannan Sadhasivam [bhelgaas: more specific subject, commit log, wrap comment to match file] Signed-off-by: Bjorn Helgaas Reviewed-by: Niklas Cassel Link: https://patch.msgid.link/20250424-pci-ep-size-alignment-v5-1-2d4ec2af23f5@baylibre.com --- drivers/pci/endpoint/pci-epf-core.c | 22 +++++++++++++++------- include/linux/pci-epf.h | 3 +++ 2 files changed, 18 insertions(+), 7 deletions(-) diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c index 394395c7f8de..577a9e490115 100644 --- a/drivers/pci/endpoint/pci-epf-core.c +++ b/drivers/pci/endpoint/pci-epf-core.c @@ -236,12 +236,13 @@ void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar, } dev = epc->dev.parent; - dma_free_coherent(dev, epf_bar[bar].size, addr, + dma_free_coherent(dev, epf_bar[bar].aligned_size, addr, epf_bar[bar].phys_addr); epf_bar[bar].phys_addr = 0; epf_bar[bar].addr = NULL; epf_bar[bar].size = 0; + epf_bar[bar].aligned_size = 0; epf_bar[bar].barno = 0; epf_bar[bar].flags = 0; } @@ -264,7 +265,7 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar, enum pci_epc_interface_type type) { u64 bar_fixed_size = epc_features->bar[bar].fixed_size; - size_t align = epc_features->align; + size_t aligned_size, align = epc_features->align; struct pci_epf_bar *epf_bar; dma_addr_t phys_addr; struct pci_epc *epc; @@ -285,12 +286,18 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar, return NULL; } size = bar_fixed_size; + } else { + /* BAR size must be power of two */ + size = roundup_pow_of_two(size); } - if (align) - size = ALIGN(size, align); - else - size = roundup_pow_of_two(size); + /* + * Allocate enough memory to accommodate the iATU alignment + * requirement. In most cases, this will be the same as .size but + * it might be different if, for example, the fixed size of a BAR + * is smaller than align. + */ + aligned_size = align ? ALIGN(size, align) : size; if (type == PRIMARY_INTERFACE) { epc = epf->epc; @@ -301,7 +308,7 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar, } dev = epc->dev.parent; - space = dma_alloc_coherent(dev, size, &phys_addr, GFP_KERNEL); + space = dma_alloc_coherent(dev, aligned_size, &phys_addr, GFP_KERNEL); if (!space) { dev_err(dev, "failed to allocate mem space\n"); return NULL; @@ -310,6 +317,7 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar, epf_bar[bar].phys_addr = phys_addr; epf_bar[bar].addr = space; epf_bar[bar].size = size; + epf_bar[bar].aligned_size = aligned_size; epf_bar[bar].barno = bar; if (upper_32_bits(size) || epc_features->bar[bar].only_64bit) epf_bar[bar].flags |= PCI_BASE_ADDRESS_MEM_TYPE_64; diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index 879d19cebd4f..749cee0bcf2c 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -114,6 +114,8 @@ struct pci_epf_driver { * @phys_addr: physical address that should be mapped to the BAR * @addr: virtual address corresponding to the @phys_addr * @size: the size of the address space present in BAR + * @aligned_size: the size actually allocated to accommodate the iATU alignment + * requirement * @barno: BAR number * @flags: flags that are set for the BAR */ @@ -121,6 +123,7 @@ struct pci_epf_bar { dma_addr_t phys_addr; void *addr; size_t size; + size_t aligned_size; enum pci_barno barno; int flags; }; From e5327a655636e2ffb93d65f44777d9481aab3715 Mon Sep 17 00:00:00 2001 From: Jerome Brunet Date: Thu, 24 Apr 2025 10:34:05 +0200 Subject: [PATCH 2/8] PCI: endpoint: pci-epf-vntb: Simplify ctrl/SPAD space allocation When allocating the shared ctrl/SPAD space, epf_ntb_config_spad_bar_alloc() should not try to handle the size quirks for underlying BAR, whether it is fixed size or alignment. This is already handled by pci_epf_alloc_space(). Also, when handling the alignment, this allocates more space than necessary. For example, with a SPAD size of 1024B and a ctrl size of 308B, the space necessary is 1332B. If the alignment is 1MB, epf_ntb_config_spad_bar_alloc() tries to allocate 2MB where 1MB would have been more than enough. Drop the handling of the BAR size quirks and let pci_epf_alloc_space() handle that. Just make sure the 32bits SPAD register are aligned on 32bits. Signed-off-by: Jerome Brunet Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Link: https://patch.msgid.link/20250424-pci-ep-size-alignment-v5-2-2d4ec2af23f5@baylibre.com --- drivers/pci/endpoint/functions/pci-epf-vntb.c | 26 +++---------------- 1 file changed, 3 insertions(+), 23 deletions(-) diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c index 874cb097b093..e4da3fdb0007 100644 --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c @@ -408,11 +408,9 @@ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb) */ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb) { - size_t align; enum pci_barno barno; struct epf_ntb_ctrl *ctrl; u32 spad_size, ctrl_size; - u64 size; struct pci_epf *epf = ntb->epf; struct device *dev = &epf->dev; u32 spad_count; @@ -422,31 +420,13 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb) epf->func_no, epf->vfunc_no); barno = ntb->epf_ntb_bar[BAR_CONFIG]; - size = epc_features->bar[barno].fixed_size; - align = epc_features->align; - - if ((!IS_ALIGNED(size, align))) - return -EINVAL; - spad_count = ntb->spad_count; - ctrl_size = sizeof(struct epf_ntb_ctrl); + ctrl_size = ALIGN(sizeof(struct epf_ntb_ctrl), sizeof(u32)); spad_size = 2 * spad_count * sizeof(u32); - if (!align) { - ctrl_size = roundup_pow_of_two(ctrl_size); - spad_size = roundup_pow_of_two(spad_size); - } else { - ctrl_size = ALIGN(ctrl_size, align); - spad_size = ALIGN(spad_size, align); - } - - if (!size) - size = ctrl_size + spad_size; - else if (size < ctrl_size + spad_size) - return -EINVAL; - - base = pci_epf_alloc_space(epf, size, barno, epc_features, 0); + base = pci_epf_alloc_space(epf, ctrl_size + spad_size, + barno, epc_features, 0); if (!base) { dev_err(dev, "Config/Status/SPAD alloc region fail\n"); return -ENOMEM; From 810276362bad172d063d1f6be1cc2cb425b90103 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Wed, 14 May 2025 09:43:14 +0200 Subject: [PATCH 3/8] PCI: dwc: ep: Correct PBA offset in .set_msix() callback While dw_pcie_ep_set_msix() writes the Table Size field correctly (N-1), the calculation of the PBA offset is wrong because it calculates space for (N-1) entries instead of N. This results in the following QEMU error when using PCI passthrough on a device which relies on the PCI endpoint subsystem: failed to add PCI capability 0x11[0x50]@0xb0: table & pba overlap, or they don't fit in BARs, or don't align Fix the calculation of PBA offset in the MSI-X capability. [bhelgaas: more specific subject and commit log] Fixes: 83153d9f36e2 ("PCI: endpoint: Fix ->set_msix() to take BIR and offset as arguments") Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Reviewed-by: Wilfred Mallawa Reviewed-by: Damien Le Moal Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250514074313.283156-9-cassel@kernel.org --- drivers/pci/controller/dwc/pcie-designware-ep.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 1a0bf9341542..24026f3f3413 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -585,6 +585,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, struct dw_pcie *pci = to_dw_pcie_from_ep(ep); struct dw_pcie_ep_func *ep_func; u32 val, reg; + u16 actual_interrupts = interrupts + 1; ep_func = dw_pcie_ep_get_func_from_ep(ep, func_no); if (!ep_func || !ep_func->msix_cap) @@ -595,7 +596,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, reg = ep_func->msix_cap + PCI_MSIX_FLAGS; val = dw_pcie_ep_readw_dbi(ep, func_no, reg); val &= ~PCI_MSIX_FLAGS_QSIZE; - val |= interrupts; + val |= interrupts; /* 0's based value */ dw_pcie_writew_dbi(pci, reg, val); reg = ep_func->msix_cap + PCI_MSIX_TABLE; @@ -603,7 +604,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, dw_pcie_ep_writel_dbi(ep, func_no, reg, val); reg = ep_func->msix_cap + PCI_MSIX_PBA; - val = (offset + (interrupts * PCI_MSIX_ENTRY_SIZE)) | bir; + val = (offset + (actual_interrupts * PCI_MSIX_ENTRY_SIZE)) | bir; dw_pcie_ep_writel_dbi(ep, func_no, reg, val); dw_pcie_dbi_ro_wr_dis(pci); From c8bcb01352a86bc5592403904109c22b66bd916e Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Wed, 14 May 2025 09:43:15 +0200 Subject: [PATCH 4/8] PCI: cadence-ep: Correct PBA offset in .set_msix() callback While cdns_pcie_ep_set_msix() writes the Table Size field correctly (N-1), the calculation of the PBA offset is wrong because it calculates space for (N-1) entries instead of N. This results in the following QEMU error when using PCI passthrough on a device which relies on the PCI endpoint subsystem: failed to add PCI capability 0x11[0x50]@0xb0: table & pba overlap, or they don't fit in BARs, or don't align Fix the calculation of PBA offset in the MSI-X capability. [bhelgaas: more specific subject and commit log] Fixes: 3ef5d16f50f8 ("PCI: cadence: Add MSI-X support to Endpoint driver") Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Reviewed-by: Wilfred Mallawa Reviewed-by: Damien Le Moal Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250514074313.283156-10-cassel@kernel.org --- drivers/pci/controller/cadence/pcie-cadence-ep.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index 599ec4b1223e..112ae200b393 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -292,13 +292,14 @@ static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn, struct cdns_pcie *pcie = &ep->pcie; u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET; u32 val, reg; + u16 actual_interrupts = interrupts + 1; fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn); reg = cap + PCI_MSIX_FLAGS; val = cdns_pcie_ep_fn_readw(pcie, fn, reg); val &= ~PCI_MSIX_FLAGS_QSIZE; - val |= interrupts; + val |= interrupts; /* 0's based value */ cdns_pcie_ep_fn_writew(pcie, fn, reg, val); /* Set MSI-X BAR and offset */ @@ -308,7 +309,7 @@ static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn, /* Set PBA BAR and offset. BAR must match MSI-X BAR */ reg = cap + PCI_MSIX_PBA; - val = (offset + (interrupts * PCI_MSIX_ENTRY_SIZE)) | bir; + val = (offset + (actual_interrupts * PCI_MSIX_ENTRY_SIZE)) | bir; cdns_pcie_ep_fn_writel(pcie, fn, reg, val); return 0; From f7f15fc53245385e39ef0aab4310d1682fd3c079 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Wed, 14 May 2025 09:43:16 +0200 Subject: [PATCH 5/8] PCI: endpoint: Align pci_epc_get_msi(), pci_epc_ops::get_msi() return value encoding The kdoc for API pci_epc_get_msi() says: "Invoke to get the number of MSI interrupts allocated by the RC" The kdoc for the callback pci_epc_ops::get_msi() says: "ops to get the number of MSI interrupts allocated by the RC from the MSI capability register" pci_epc_ops::get_msi() does however return the number of interrupts in the encoding as defined by the Multiple Message Enable (MME) field of the MSI Capability structure. Nowhere in the kdoc does it say that the returned number of interrupts is in MME encoding. It is very confusing that the API pci_epc_get_msi() and the callback function pci_epc_ops::get_msi() don't return the same value. Clean up the API and the callback function to have the same semantics, i.e. return the number of interrupts, regardless of the internal encoding of that value. [bhelgaas: more specific subject] Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Reviewed-by: Damien Le Moal Cc: stable+noautosel@kernel.org # this is simply a cleanup Link: https://patch.msgid.link/20250514074313.283156-11-cassel@kernel.org --- drivers/pci/controller/cadence/pcie-cadence-ep.c | 2 +- drivers/pci/controller/dwc/pcie-designware-ep.c | 2 +- drivers/pci/controller/pcie-rcar-ep.c | 2 +- drivers/pci/controller/pcie-rockchip-ep.c | 4 ++-- drivers/pci/endpoint/pci-epc-core.c | 2 -- 5 files changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index 112ae200b393..78b4d009cd04 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -262,7 +262,7 @@ static int cdns_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn) */ mme = FIELD_GET(PCI_MSI_FLAGS_QSIZE, flags); - return mme; + return 1 << mme; } static int cdns_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no) diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 24026f3f3413..03597551f4cd 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -532,7 +532,7 @@ static int dw_pcie_ep_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no) val = FIELD_GET(PCI_MSI_FLAGS_QSIZE, val); - return val; + return 1 << val; } static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c index c5e0d025bc43..9da39a4617b6 100644 --- a/drivers/pci/controller/pcie-rcar-ep.c +++ b/drivers/pci/controller/pcie-rcar-ep.c @@ -280,7 +280,7 @@ static int rcar_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn) if (!(flags & MSICAP0_MSIE)) return -EINVAL; - return ((flags & MSICAP0_MMESE_MASK) >> MSICAP0_MMESE_OFFSET); + return 1 << ((flags & MSICAP0_MMESE_MASK) >> MSICAP0_MMESE_OFFSET); } static int rcar_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, u8 vfn, diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c index 85ea36df2f59..85ca7d9b4c77 100644 --- a/drivers/pci/controller/pcie-rockchip-ep.c +++ b/drivers/pci/controller/pcie-rockchip-ep.c @@ -340,8 +340,8 @@ static int rockchip_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn) if (!(flags & ROCKCHIP_PCIE_EP_MSI_CTRL_ME)) return -EINVAL; - return ((flags & ROCKCHIP_PCIE_EP_MSI_CTRL_MME_MASK) >> - ROCKCHIP_PCIE_EP_MSI_CTRL_MME_OFFSET); + return 1 << ((flags & ROCKCHIP_PCIE_EP_MSI_CTRL_MME_MASK) >> + ROCKCHIP_PCIE_EP_MSI_CTRL_MME_OFFSET); } static void rockchip_pcie_ep_assert_intx(struct rockchip_pcie_ep *ep, u8 fn, diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index beabea00af91..cc1456bd188e 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -293,8 +293,6 @@ int pci_epc_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no) if (interrupt < 0) return 0; - interrupt = 1 << interrupt; - return interrupt; } EXPORT_SYMBOL_GPL(pci_epc_get_msi); From 0917ed8f16b646c5e3cc481ccfa4709286b76691 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Wed, 14 May 2025 09:43:17 +0200 Subject: [PATCH 6/8] PCI: endpoint: Align pci_epc_get_msix(), pci_epc_ops::get_msix() return value encoding The kdoc for pci_epc_get_msix() says: "Invoke to get the number of MSI-X interrupts allocated by the RC" The kdoc for the callback pci_epc_ops->get_msix() says: "ops to get the number of MSI-X interrupts allocated by the RC from the MSI-X capability register" pci_epc_ops::get_msix() does however return the number of interrupts in the encoding as defined by the Table Size field. Nowhere in the kdoc does it say that the returned number of interrupts is in Table Size encoding. It is very confusing that the API pci_epc_get_msix() and the callback function pci_epc_ops::get_msix() don't return the same value. Clean up the API and the callback function to have the same semantics, i.e. return the number of interrupts, regardless of the internal encoding of that value. [bhelgaas: more specific subject] Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Reviewed-by: Damien Le Moal Cc: stable+noautosel@kernel.org # this is simply a cleanup Link: https://patch.msgid.link/20250514074313.283156-12-cassel@kernel.org --- drivers/pci/controller/cadence/pcie-cadence-ep.c | 2 +- drivers/pci/controller/dwc/pcie-designware-ep.c | 2 +- drivers/pci/endpoint/pci-epc-core.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index 78b4d009cd04..569cb7481d45 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -281,7 +281,7 @@ static int cdns_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no) val &= PCI_MSIX_FLAGS_QSIZE; - return val; + return val + 1; } static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn, diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 03597551f4cd..307c862588a4 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -575,7 +575,7 @@ static int dw_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no) val &= PCI_MSIX_FLAGS_QSIZE; - return val; + return val + 1; } static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index cc1456bd188e..092b14918b46 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -355,7 +355,7 @@ int pci_epc_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no) if (interrupt < 0) return 0; - return interrupt + 1; + return interrupt; } EXPORT_SYMBOL_GPL(pci_epc_get_msix); From f62da6e7270c2db5aef8a8b14f465896961a9372 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Wed, 14 May 2025 09:43:18 +0200 Subject: [PATCH 7/8] PCI: endpoint: Align pci_epc_set_msi(), pci_epc_ops::set_msi() nr_irqs encoding The kdoc for pci_epc_set_msi() says: "Invoke to set the required number of MSI interrupts." The kdoc for the callback pci_epc_ops::set_msi() says: "ops to set the requested number of MSI interrupts in the MSI capability register" pci_epc_ops::set_msi() does however expect the parameter 'interrupts' to be in the encoding as defined by the Multiple Message Capable (MMC) field of the MSI capability structure. Nowhere in the kdoc does it say that the number of interrupts should be in MMC encoding. It is very confusing that the API pci_epc_set_msi() and the callback function pci_epc_ops::set_msi() both take a parameter named 'interrupts', but they expect completely different encodings. Clean up the API and the callback function to have the same semantics, i.e. the parameter represents the number of interrupts, regardless of the internal encoding of that value. Also rename the parameter 'interrupts' to 'nr_irqs', in both the wrapper function and the callback function, such that the name is unambiguous. [bhelgaas: more specific subject] Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Cc: stable+noautosel@kernel.org # this is simply a cleanup Link: https://patch.msgid.link/20250514074313.283156-13-cassel@kernel.org --- drivers/pci/controller/cadence/pcie-cadence-ep.c | 3 ++- drivers/pci/controller/dwc/pcie-designware-ep.c | 5 +++-- drivers/pci/controller/pcie-rcar-ep.c | 6 +++--- drivers/pci/controller/pcie-rockchip-ep.c | 5 +++-- drivers/pci/endpoint/pci-epc-core.c | 11 ++++------- include/linux/pci-epc.h | 5 ++--- 6 files changed, 17 insertions(+), 18 deletions(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index 569cb7481d45..f09f29ed27ed 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -220,10 +220,11 @@ static void cdns_pcie_ep_unmap_addr(struct pci_epc *epc, u8 fn, u8 vfn, clear_bit(r, &ep->ob_region_map); } -static int cdns_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, u8 mmc) +static int cdns_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, u8 nr_irqs) { struct cdns_pcie_ep *ep = epc_get_drvdata(epc); struct cdns_pcie *pcie = &ep->pcie; + u8 mmc = order_base_2(nr_irqs); u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET; u16 flags; diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 307c862588a4..230e82674591 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -536,11 +536,12 @@ static int dw_pcie_ep_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no) } static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, - u8 interrupts) + u8 nr_irqs) { struct dw_pcie_ep *ep = epc_get_drvdata(epc); struct dw_pcie *pci = to_dw_pcie_from_ep(ep); struct dw_pcie_ep_func *ep_func; + u8 mmc = order_base_2(nr_irqs); u32 val, reg; ep_func = dw_pcie_ep_get_func_from_ep(ep, func_no); @@ -550,7 +551,7 @@ static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, reg = ep_func->msi_cap + PCI_MSI_FLAGS; val = dw_pcie_ep_readw_dbi(ep, func_no, reg); val &= ~PCI_MSI_FLAGS_QMASK; - val |= FIELD_PREP(PCI_MSI_FLAGS_QMASK, interrupts); + val |= FIELD_PREP(PCI_MSI_FLAGS_QMASK, mmc); dw_pcie_dbi_ro_wr_en(pci); dw_pcie_ep_writew_dbi(ep, func_no, reg, val); dw_pcie_dbi_ro_wr_dis(pci); diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c index 9da39a4617b6..a8a966844cf3 100644 --- a/drivers/pci/controller/pcie-rcar-ep.c +++ b/drivers/pci/controller/pcie-rcar-ep.c @@ -256,15 +256,15 @@ static void rcar_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn, u8 vfn, clear_bit(atu_index + 1, ep->ib_window_map); } -static int rcar_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, - u8 interrupts) +static int rcar_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, u8 nr_irqs) { struct rcar_pcie_endpoint *ep = epc_get_drvdata(epc); struct rcar_pcie *pcie = &ep->pcie; + u8 mmc = order_base_2(nr_irqs); u32 flags; flags = rcar_pci_read_reg(pcie, MSICAP(fn)); - flags |= interrupts << MSICAP0_MMESCAP_OFFSET; + flags |= mmc << MSICAP0_MMESCAP_OFFSET; rcar_pci_write_reg(pcie, flags, MSICAP(fn)); return 0; diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c index 85ca7d9b4c77..a0a85080c31d 100644 --- a/drivers/pci/controller/pcie-rockchip-ep.c +++ b/drivers/pci/controller/pcie-rockchip-ep.c @@ -308,10 +308,11 @@ static void rockchip_pcie_ep_unmap_addr(struct pci_epc *epc, u8 fn, u8 vfn, } static int rockchip_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, - u8 multi_msg_cap) + u8 nr_irqs) { struct rockchip_pcie_ep *ep = epc_get_drvdata(epc); struct rockchip_pcie *rockchip = &ep->rockchip; + u8 mmc = order_base_2(nr_irqs); u32 flags; flags = rockchip_pcie_read(rockchip, @@ -319,7 +320,7 @@ static int rockchip_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, ROCKCHIP_PCIE_EP_MSI_CTRL_REG); flags &= ~ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_MASK; flags |= - (multi_msg_cap << ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_OFFSET) | + (mmc << ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_OFFSET) | (PCI_MSI_FLAGS_64BIT << ROCKCHIP_PCIE_EP_MSI_FLAGS_OFFSET); flags &= ~ROCKCHIP_PCIE_EP_MSI_CTRL_MASK_MSI_CAP; rockchip_pcie_write(rockchip, flags, diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index 092b14918b46..ea698551f9d8 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -302,28 +302,25 @@ EXPORT_SYMBOL_GPL(pci_epc_get_msi); * @epc: the EPC device on which MSI has to be configured * @func_no: the physical endpoint function number in the EPC device * @vfunc_no: the virtual endpoint function number in the physical function - * @interrupts: number of MSI interrupts required by the EPF + * @nr_irqs: number of MSI interrupts required by the EPF * * Invoke to set the required number of MSI interrupts. */ -int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u8 interrupts) +int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u8 nr_irqs) { int ret; - u8 encode_int; if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) return -EINVAL; - if (interrupts < 1 || interrupts > 32) + if (nr_irqs < 1 || nr_irqs > 32) return -EINVAL; if (!epc->ops->set_msi) return 0; - encode_int = order_base_2(interrupts); - mutex_lock(&epc->lock); - ret = epc->ops->set_msi(epc, func_no, vfunc_no, encode_int); + ret = epc->ops->set_msi(epc, func_no, vfunc_no, nr_irqs); mutex_unlock(&epc->lock); return ret; diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 82837008b56f..15d10c07c9f1 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -100,7 +100,7 @@ struct pci_epc_ops { void (*unmap_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, phys_addr_t addr); int (*set_msi)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, - u8 interrupts); + u8 nr_irqs); int (*get_msi)(struct pci_epc *epc, u8 func_no, u8 vfunc_no); int (*set_msix)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u16 interrupts, enum pci_barno, u32 offset); @@ -286,8 +286,7 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u64 pci_addr, size_t size); void pci_epc_unmap_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no, phys_addr_t phys_addr); -int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, - u8 interrupts); +int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u8 nr_irqs); int pci_epc_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no); int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u16 interrupts, enum pci_barno, u32 offset); From de0321bcc5fdd83631f0c2a6fdebfe0ad4e23449 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Wed, 14 May 2025 09:43:19 +0200 Subject: [PATCH 8/8] PCI: endpoint: Align pci_epc_set_msix(), pci_epc_ops::set_msix() nr_irqs encoding The kdoc for pci_epc_set_msix() says: "Invoke to set the required number of MSI-X interrupts." The kdoc for the callback pci_epc_ops->set_msix() says: "ops to set the requested number of MSI-X interrupts in the MSI-X capability register" pci_epc_ops::set_msix() does however expect the parameter 'interrupts' to be in the encoding as defined by the Table Size field. Nowhere in the kdoc does it say that the number of interrupts should be in Table Size encoding. It is very confusing that the API pci_epc_set_msix() and the callback function pci_epc_ops::set_msix() both take a parameter named 'interrupts', but they expect completely different encodings. Clean up the API and the callback function to have the same semantics, i.e. the parameter represents the number of interrupts, regardless of the internal encoding of that value. Also rename the parameter 'interrupts' to 'nr_irqs', in both the wrapper function and the callback function, such that the name is unambiguous. [bhelgaas: more specific subject] Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Cc: stable+noautosel@kernel.org # this is simply a cleanup Link: https://patch.msgid.link/20250514074313.283156-14-cassel@kernel.org --- drivers/pci/controller/cadence/pcie-cadence-ep.c | 8 +++----- drivers/pci/controller/dwc/pcie-designware-ep.c | 7 +++---- drivers/pci/endpoint/pci-epc-core.c | 11 +++++------ include/linux/pci-epc.h | 6 +++--- 4 files changed, 14 insertions(+), 18 deletions(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index f09f29ed27ed..0e9ebe956e7a 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -286,21 +286,19 @@ static int cdns_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no) } static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn, - u16 interrupts, enum pci_barno bir, - u32 offset) + u16 nr_irqs, enum pci_barno bir, u32 offset) { struct cdns_pcie_ep *ep = epc_get_drvdata(epc); struct cdns_pcie *pcie = &ep->pcie; u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET; u32 val, reg; - u16 actual_interrupts = interrupts + 1; fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn); reg = cap + PCI_MSIX_FLAGS; val = cdns_pcie_ep_fn_readw(pcie, fn, reg); val &= ~PCI_MSIX_FLAGS_QSIZE; - val |= interrupts; /* 0's based value */ + val |= nr_irqs - 1; /* encoded as N-1 */ cdns_pcie_ep_fn_writew(pcie, fn, reg, val); /* Set MSI-X BAR and offset */ @@ -310,7 +308,7 @@ static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn, /* Set PBA BAR and offset. BAR must match MSI-X BAR */ reg = cap + PCI_MSIX_PBA; - val = (offset + (actual_interrupts * PCI_MSIX_ENTRY_SIZE)) | bir; + val = (offset + (nr_irqs * PCI_MSIX_ENTRY_SIZE)) | bir; cdns_pcie_ep_fn_writel(pcie, fn, reg, val); return 0; diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 230e82674591..6770318c0636 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -580,13 +580,12 @@ static int dw_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no) } static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, - u16 interrupts, enum pci_barno bir, u32 offset) + u16 nr_irqs, enum pci_barno bir, u32 offset) { struct dw_pcie_ep *ep = epc_get_drvdata(epc); struct dw_pcie *pci = to_dw_pcie_from_ep(ep); struct dw_pcie_ep_func *ep_func; u32 val, reg; - u16 actual_interrupts = interrupts + 1; ep_func = dw_pcie_ep_get_func_from_ep(ep, func_no); if (!ep_func || !ep_func->msix_cap) @@ -597,7 +596,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, reg = ep_func->msix_cap + PCI_MSIX_FLAGS; val = dw_pcie_ep_readw_dbi(ep, func_no, reg); val &= ~PCI_MSIX_FLAGS_QSIZE; - val |= interrupts; /* 0's based value */ + val |= nr_irqs - 1; /* encoded as N-1 */ dw_pcie_writew_dbi(pci, reg, val); reg = ep_func->msix_cap + PCI_MSIX_TABLE; @@ -605,7 +604,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, dw_pcie_ep_writel_dbi(ep, func_no, reg, val); reg = ep_func->msix_cap + PCI_MSIX_PBA; - val = (offset + (actual_interrupts * PCI_MSIX_ENTRY_SIZE)) | bir; + val = (offset + (nr_irqs * PCI_MSIX_ENTRY_SIZE)) | bir; dw_pcie_ep_writel_dbi(ep, func_no, reg, val); dw_pcie_dbi_ro_wr_dis(pci); diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index ea698551f9d8..ca7f19cc973a 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -361,29 +361,28 @@ EXPORT_SYMBOL_GPL(pci_epc_get_msix); * @epc: the EPC device on which MSI-X has to be configured * @func_no: the physical endpoint function number in the EPC device * @vfunc_no: the virtual endpoint function number in the physical function - * @interrupts: number of MSI-X interrupts required by the EPF + * @nr_irqs: number of MSI-X interrupts required by the EPF * @bir: BAR where the MSI-X table resides * @offset: Offset pointing to the start of MSI-X table * * Invoke to set the required number of MSI-X interrupts. */ -int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, - u16 interrupts, enum pci_barno bir, u32 offset) +int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u16 nr_irqs, + enum pci_barno bir, u32 offset) { int ret; if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) return -EINVAL; - if (interrupts < 1 || interrupts > 2048) + if (nr_irqs < 1 || nr_irqs > 2048) return -EINVAL; if (!epc->ops->set_msix) return 0; mutex_lock(&epc->lock); - ret = epc->ops->set_msix(epc, func_no, vfunc_no, interrupts - 1, bir, - offset); + ret = epc->ops->set_msix(epc, func_no, vfunc_no, nr_irqs, bir, offset); mutex_unlock(&epc->lock); return ret; diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 15d10c07c9f1..4286bfdbfdfa 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -103,7 +103,7 @@ struct pci_epc_ops { u8 nr_irqs); int (*get_msi)(struct pci_epc *epc, u8 func_no, u8 vfunc_no); int (*set_msix)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, - u16 interrupts, enum pci_barno, u32 offset); + u16 nr_irqs, enum pci_barno, u32 offset); int (*get_msix)(struct pci_epc *epc, u8 func_no, u8 vfunc_no); int (*raise_irq)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, unsigned int type, u16 interrupt_num); @@ -288,8 +288,8 @@ void pci_epc_unmap_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no, phys_addr_t phys_addr); int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u8 nr_irqs); int pci_epc_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no); -int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, - u16 interrupts, enum pci_barno, u32 offset); +int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u16 nr_irqs, + enum pci_barno, u32 offset); int pci_epc_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no); int pci_epc_map_msi_irq(struct pci_epc *epc, u8 func_no, u8 vfunc_no, phys_addr_t phys_addr, u8 interrupt_num,