git: 6c321dc15d52 - stable/15 - nvme: Add handling for bar5

The branch stable/15 has been updated by ziaee:

URL: https://cgit.FreeBSD.org/src/commit/?id=6c321dc15d5234742c6452e975f41f4a24b52e1d

commit 6c321dc15d5234742c6452e975f41f4a24b52e1d
Author:     Jasper Tran O'Leary <jtranoleary@google.com>
AuthorDate: 2025-10-28 20:43:35 +0000
Commit:     Alexander Ziaee <ziaee@FreeBSD.org>
CommitDate: 2025-11-03 22:04:30 +0000

    nvme: Add handling for bar5
    
    The NVMe spec allows the Table BIR (TBIR) and PBA DIR (PBIR) to
    be 0, 4, or 5. The existing NVMe driver basically only has support
    for 4, perhaps under the assumption that BAR4 is 64-bit and also
    occupies BAR5.
    
    This change adds support for BAR5, covering the case where BAR4
    and BAR5 might both be present and 32-bit, where the Table BIR
    might be 4 and the PBA BIR might be 5, or vice versa.
    
    The NVMe spec (in the SR-IOV section) also permits VFs to use BIR=2,
    so I haven't added stricter checks on which BIR will be permitted
    by the driver.
    
    This enables FreeBSD on Google Compute Engine C4 Machines.
    
    MFC after:              3 days
    Reviewed by:            imp
    Sponsored by:           Google
    Co-authored-by:         Matt Delco <delco@google.com>
    Signed-off-by:          Jasper Tran O'Leary <jtranoleary@google.com>
    Differential Revision:  https://reviews.freebsd.org/D53140
    
    (cherry picked from commit 7b32f4f0a7fe9b1b2f5a3905ca15f656713255ad)
---
 sys/dev/nvme/nvme_ctrlr.c   |  9 +++++++--
 sys/dev/nvme/nvme_pci.c     | 48 ++++++++++++++++++++++++++++++++++-----------
 sys/dev/nvme/nvme_private.h |  6 ++++--
 3 files changed, 48 insertions(+), 15 deletions(-)

diff --git a/sys/dev/nvme/nvme_ctrlr.c b/sys/dev/nvme/nvme_ctrlr.c
index fc912c1342f4..6ed9cb33f991 100644
--- a/sys/dev/nvme/nvme_ctrlr.c
+++ b/sys/dev/nvme/nvme_ctrlr.c
@@ -1746,9 +1746,14 @@ noadminq:
 		bus_release_resource(ctrlr->dev, SYS_RES_IRQ,
 		    rman_get_rid(ctrlr->res), ctrlr->res);
 
-	if (ctrlr->bar4_resource != NULL) {
+	if (ctrlr->msix_table_resource != NULL) {
 		bus_release_resource(dev, SYS_RES_MEMORY,
-		    ctrlr->bar4_resource_id, ctrlr->bar4_resource);
+		    ctrlr->msix_table_resource_id, ctrlr->msix_table_resource);
+	}
+
+	if (ctrlr->msix_pba_resource != NULL) {
+		bus_release_resource(dev, SYS_RES_MEMORY,
+		    ctrlr->msix_pba_resource_id, ctrlr->msix_pba_resource);
 	}
 
 	bus_release_resource(dev, SYS_RES_MEMORY,
diff --git a/sys/dev/nvme/nvme_pci.c b/sys/dev/nvme/nvme_pci.c
index c07a68d2f0dc..cecb05ca0a92 100644
--- a/sys/dev/nvme/nvme_pci.c
+++ b/sys/dev/nvme/nvme_pci.c
@@ -152,11 +152,15 @@ static int
 nvme_ctrlr_allocate_bar(struct nvme_controller *ctrlr)
 {
 	ctrlr->resource_id = PCIR_BAR(0);
+	ctrlr->msix_table_resource_id = -1;
+	ctrlr->msix_table_resource = NULL;
+	ctrlr->msix_pba_resource_id = -1;
+	ctrlr->msix_pba_resource = NULL;
 
 	ctrlr->resource = bus_alloc_resource_any(ctrlr->dev, SYS_RES_MEMORY,
 	    &ctrlr->resource_id, RF_ACTIVE);
 
-	if(ctrlr->resource == NULL) {
+	if (ctrlr->resource == NULL) {
 		nvme_printf(ctrlr, "unable to allocate pci resource\n");
 		return (ENOMEM);
 	}
@@ -166,15 +170,32 @@ nvme_ctrlr_allocate_bar(struct nvme_controller *ctrlr)
 	ctrlr->regs = (struct nvme_registers *)ctrlr->bus_handle;
 
 	/*
-	 * The NVMe spec allows for the MSI-X table to be placed behind
-	 *  BAR 4/5, separate from the control/doorbell registers.  Always
-	 *  try to map this bar, because it must be mapped prior to calling
-	 *  pci_alloc_msix().  If the table isn't behind BAR 4/5,
-	 *  bus_alloc_resource() will just return NULL which is OK.
+	 * The NVMe spec allows for the MSI-X tables to be placed behind
+	 *  BAR 4 and/or 5, separate from the control/doorbell registers.
 	 */
-	ctrlr->bar4_resource_id = PCIR_BAR(4);
-	ctrlr->bar4_resource = bus_alloc_resource_any(ctrlr->dev, SYS_RES_MEMORY,
-	    &ctrlr->bar4_resource_id, RF_ACTIVE);
+
+	ctrlr->msix_table_resource_id = pci_msix_table_bar(ctrlr->dev);
+	ctrlr->msix_pba_resource_id = pci_msix_pba_bar(ctrlr->dev);
+
+	if (ctrlr->msix_table_resource_id >= 0 &&
+	    ctrlr->msix_table_resource_id != ctrlr->resource_id) {
+		ctrlr->msix_table_resource = bus_alloc_resource_any(ctrlr->dev,
+		    SYS_RES_MEMORY, &ctrlr->msix_table_resource_id, RF_ACTIVE);
+		if (ctrlr->msix_table_resource == NULL) {
+			nvme_printf(ctrlr, "unable to allocate msi-x table resource\n");
+			return (ENOMEM);
+		}
+	}
+	if (ctrlr->msix_pba_resource_id >= 0 &&
+	    ctrlr->msix_pba_resource_id != ctrlr->resource_id &&
+	    ctrlr->msix_pba_resource_id != ctrlr->msix_table_resource_id) {
+		ctrlr->msix_pba_resource = bus_alloc_resource_any(ctrlr->dev,
+		    SYS_RES_MEMORY, &ctrlr->msix_pba_resource_id, RF_ACTIVE);
+		if (ctrlr->msix_pba_resource == NULL) {
+			nvme_printf(ctrlr, "unable to allocate msi-x pba resource\n");
+			return (ENOMEM);
+		}
+	}
 
 	return (0);
 }
@@ -200,9 +221,14 @@ bad:
 		    ctrlr->resource_id, ctrlr->resource);
 	}
 
-	if (ctrlr->bar4_resource != NULL) {
+	if (ctrlr->msix_table_resource != NULL) {
+		bus_release_resource(dev, SYS_RES_MEMORY,
+		    ctrlr->msix_table_resource_id, ctrlr->msix_table_resource);
+	}
+
+	if (ctrlr->msix_pba_resource != NULL) {
 		bus_release_resource(dev, SYS_RES_MEMORY,
-		    ctrlr->bar4_resource_id, ctrlr->bar4_resource);
+		    ctrlr->msix_pba_resource_id, ctrlr->msix_pba_resource);
 	}
 
 	if (ctrlr->tag)
diff --git a/sys/dev/nvme/nvme_private.h b/sys/dev/nvme/nvme_private.h
index 52e9fcbbebcd..a425a6a5ad62 100644
--- a/sys/dev/nvme/nvme_private.h
+++ b/sys/dev/nvme/nvme_private.h
@@ -235,8 +235,10 @@ struct nvme_controller {
 	 *  separate from the control registers which are in BAR 0/1.  These
 	 *  members track the mapping of BAR 4/5 for that reason.
 	 */
-	int			bar4_resource_id;
-	struct resource		*bar4_resource;
+	int			msix_table_resource_id;
+	struct resource		*msix_table_resource;
+	int			msix_pba_resource_id;
+	struct resource		*msix_pba_resource;
 
 	int			msi_count;
 	uint32_t		enable_aborts;