From 21f6adec073f89bf953fb17ddf388399a659efce Mon Sep 17 00:00:00 2001 From: Haiyue Wang Date: Mon, 24 May 2021 09:23:43 +0800 Subject: [PATCH] bus/pci: configure PCI bus master Add the API to set 'Bus Master Enable' bit to be enabled or disabled in the PCI command register. Signed-off-by: Haiyue Wang Acked-by: Ray Kinsella --- drivers/bus/pci/pci_common.c | 28 ++++++++++++++++++++++++++++ drivers/bus/pci/rte_bus_pci.h | 14 ++++++++++++++ drivers/bus/pci/version.map | 3 +++ lib/pci/rte_pci.h | 4 ++++ 4 files changed, 49 insertions(+) diff --git a/drivers/bus/pci/pci_common.c b/drivers/bus/pci/pci_common.c index ee7f966358..35d7d092d1 100644 --- a/drivers/bus/pci/pci_common.c +++ b/drivers/bus/pci/pci_common.c @@ -746,6 +746,34 @@ rte_pci_find_ext_capability(struct rte_pci_device *dev, uint32_t cap) return 0; } +int +rte_pci_set_bus_master(struct rte_pci_device *dev, bool enable) +{ + uint16_t old_cmd, cmd; + + if (rte_pci_read_config(dev, &old_cmd, sizeof(old_cmd), + RTE_PCI_COMMAND) < 0) { + RTE_LOG(ERR, EAL, "error in reading PCI command register\n"); + return -1; + } + + if (enable) + cmd = old_cmd | RTE_PCI_COMMAND_MASTER; + else + cmd = old_cmd & ~RTE_PCI_COMMAND_MASTER; + + if (cmd == old_cmd) + return 0; + + if (rte_pci_write_config(dev, &cmd, sizeof(cmd), + RTE_PCI_COMMAND) < 0) { + RTE_LOG(ERR, EAL, "error in writing PCI command register\n"); + return -1; + } + + return 0; +} + struct rte_pci_bus rte_pci_bus = { .bus = { .scan = rte_pci_scan, diff --git a/drivers/bus/pci/rte_bus_pci.h b/drivers/bus/pci/rte_bus_pci.h index 64886b4731..976c33c921 100644 --- a/drivers/bus/pci/rte_bus_pci.h +++ b/drivers/bus/pci/rte_bus_pci.h @@ -249,6 +249,20 @@ void rte_pci_dump(FILE *f); __rte_experimental off_t rte_pci_find_ext_capability(struct rte_pci_device *dev, uint32_t cap); +/** + * Enables/Disables Bus Master for device's PCI command register. + * + * @param dev + * A pointer to rte_pci_device structure. + * @param enable + * Enable or disable Bus Master. + * + * @return + * 0 on success, -1 on error in PCI config space read/write. + */ +__rte_experimental +int rte_pci_set_bus_master(struct rte_pci_device *dev, bool enable); + /** * Register a PCI driver. * diff --git a/drivers/bus/pci/version.map b/drivers/bus/pci/version.map index f33ed0abd1..00fac8864c 100644 --- a/drivers/bus/pci/version.map +++ b/drivers/bus/pci/version.map @@ -21,4 +21,7 @@ EXPERIMENTAL { global: rte_pci_find_ext_capability; + + # added in 21.08 + rte_pci_set_bus_master; }; diff --git a/lib/pci/rte_pci.h b/lib/pci/rte_pci.h index a8f8e404a9..1f33d687f4 100644 --- a/lib/pci/rte_pci.h +++ b/lib/pci/rte_pci.h @@ -32,6 +32,10 @@ extern "C" { #define RTE_PCI_VENDOR_ID 0x00 /* 16 bits */ #define RTE_PCI_DEVICE_ID 0x02 /* 16 bits */ +#define RTE_PCI_COMMAND 0x04 /* 16 bits */ + +/* PCI Command Register */ +#define RTE_PCI_COMMAND_MASTER 0x4 /* Bus Master Enable */ /* PCI Express capability registers */ #define RTE_PCI_EXP_DEVCTL 8 /* Device Control */ -- 2.20.1