[RFC PATCH v3 07/35] PCI: endpoint: pci-epf-vntb: Hint subrange mapping preference to EPC driver
From: Koichiro Den <hidden>
Date: 2025-12-17 19:13:43
Also in:
dmaengine, linux-pci, linux-renesas-soc, lkml
Subsystem:
ntb driver core, pci endpoint subsystem, pci subsystem, the rest · Maintainers:
Jon Mason, Dave Jiang, Allen Hubbe, Manivannan Sadhasivam, Krzysztof Wilczyński, Bjorn Helgaas, Linus Torvalds
Now that pci_epc_set_bar supports subrange mapping, give a hint about that when calling pci_epc_set_bar(). For example, DW EPC chooses Address Match Mode IB iATU mapping when 'use_submap' is set to true. Signed-off-by: Koichiro Den <redacted> --- drivers/pci/endpoint/functions/pci-epf-vntb.c | 30 ++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 337995e2f3ce..23bbcfd20c3b 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c@@ -731,6 +731,12 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb) PCI_BASE_ADDRESS_MEM_TYPE_64 : PCI_BASE_ADDRESS_MEM_TYPE_32; + /* express preference for subrange mapping */ + ntb->epf->bar[barno].use_submap = true; + ntb->epf->bar[barno].num_submap = 0; + if (WARN_ON(ntb->epf->bar[barno].submap)) + dev_warn(dev, "BAR%u submap is not NULL\n", barno); + ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no,
@@ -1391,6 +1397,7 @@ static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx, enum pci_barno barno; int ret; struct device *dev; + unsigned int sb; dev = &ntb->ntb.dev; barno = ntb->epf_ntb_bar[BAR_MW1 + idx];
@@ -1399,7 +1406,28 @@ static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx, epf_bar->barno = barno; epf_bar->size = size; - ret = pci_epc_set_bar(ntb->epf->epc, 0, 0, epf_bar); + /* express preference for subrange mapping */ + epf_bar->use_submap = true; + for (sb = 0; sb < epf_bar->num_submap; sb++) { + if (epf_bar->submap[sb].offset == offset) { + dev_warn(dev, "offset 0x%llx is already mapped\n", + offset); + return -EBUSY; + } + } + epf_bar->num_submap++; + epf_bar->submap = devm_krealloc_array( + &ntb->epf->dev, epf_bar->submap, + epf_bar->num_submap, sizeof(*epf_bar->submap), + GFP_KERNEL); + if (!epf_bar->submap) + return -ENOMEM; + epf_bar->submap[sb].phys_addr = addr; + epf_bar->submap[sb].size = size; + epf_bar->submap[sb].offset = offset; + + ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no, + ntb->epf->vfunc_no, epf_bar); if (ret) { dev_err(dev, "failure set mw trans\n"); return ret;
--
2.51.0