[PATCH v4 4/7] PCI: Allow IOV resources to be resized in pci_resize_resource()
Michał Winiarski
michal.winiarski at intel.com
Fri Oct 25 21:50:35 UTC 2024
Similar to regular resizable BAR, VF BAR can also be resized.
The structures are very similar, which means we can reuse most of the
implementation.
Extend the pci_resize_resource() function to accept IOV resources.
See PCIe r4.0, sec 9.3.7.4.
Signed-off-by: Michał Winiarski <michal.winiarski at intel.com>
---
drivers/pci/iov.c | 21 +++++++++++++++++++++
drivers/pci/pci.c | 10 +++++++++-
drivers/pci/pci.h | 10 +++++++++-
drivers/pci/setup-res.c | 36 +++++++++++++++++++++++++++++++-----
4 files changed, 70 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index eedc1df56c49e..79143c1bc7bb4 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -154,6 +154,27 @@ resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
return dev->sriov->barsz[pci_resource_from_iov(resno)];
}
+void pci_iov_resource_set_size(struct pci_dev *dev, int resno,
+ resource_size_t size)
+{
+ if (!pci_resource_is_iov(resno)) {
+ pci_warn(dev, "%s is not an IOV resource\n",
+ pci_resource_name(dev, resno));
+ return;
+ }
+
+ dev->sriov->barsz[pci_resource_from_iov(resno)] = size;
+}
+
+bool pci_iov_is_memory_decoding_enabled(struct pci_dev *dev)
+{
+ u16 cmd;
+
+ pci_read_config_word(dev, dev->sriov->pos + PCI_SRIOV_CTRL, &cmd);
+
+ return cmd & PCI_SRIOV_CTRL_MSE;
+}
+
static void pci_read_vf_config_common(struct pci_dev *virtfn)
{
struct pci_dev *physfn = virtfn->physfn;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7d85c04fbba2a..905a533807b32 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3720,8 +3720,16 @@ static int pci_rebar_find_pos(struct pci_dev *pdev, int bar)
{
unsigned int pos, nbars, i;
u32 ctrl;
+ int cap;
- pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_REBAR);
+ if (pci_resource_is_iov(bar)) {
+ cap = PCI_EXT_CAP_ID_VF_REBAR;
+ bar = pci_resource_from_iov(bar);
+ } else {
+ cap = PCI_EXT_CAP_ID_REBAR;
+ }
+
+ pos = pci_find_ext_capability(pdev, cap);
if (!pos)
return -ENOTSUPP;
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 1f8d88f0243b7..4347858007145 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -580,6 +580,9 @@ void pci_iov_update_resource(struct pci_dev *dev, int resno);
resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno);
void pci_restore_iov_state(struct pci_dev *dev);
int pci_iov_bus_range(struct pci_bus *bus);
+void pci_iov_resource_set_size(struct pci_dev *dev, int resno,
+ resource_size_t size);
+bool pci_iov_is_memory_decoding_enabled(struct pci_dev *dev);
static inline bool pci_resource_is_iov(int resno)
{
return resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END;
@@ -613,6 +616,12 @@ static inline int pci_iov_bus_range(struct pci_bus *bus)
{
return 0;
}
+static inline void pci_iov_resource_set_size(struct pci_dev *dev, int resno,
+ resource_size_t size) { }
+static inline bool pci_iov_is_memory_decoding_enabled(struct pci_dev *dev)
+{
+ return false;
+}
static inline bool pci_resource_is_iov(int resno)
{
return false;
@@ -621,7 +630,6 @@ static inline int pci_resource_to_iov(int resno)
{
return -ENODEV;
}
-
static inline int pci_resource_from_iov(int resno)
{
return -ENODEV;
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index e2cf79253ebda..cec8f684b7c70 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -425,13 +425,40 @@ void pci_release_resource(struct pci_dev *dev, int resno)
}
EXPORT_SYMBOL(pci_release_resource);
+static bool pci_resize_is_memory_decoding_enabled(struct pci_dev *dev,
+ int resno)
+{
+ u16 cmd;
+
+ if (pci_resource_is_iov(resno))
+ return pci_iov_is_memory_decoding_enabled(dev);
+
+ pci_read_config_word(dev, PCI_COMMAND, &cmd);
+
+ return cmd & PCI_COMMAND_MEMORY;
+}
+
+static void pci_resize_resource_set_size(struct pci_dev *dev, int resno,
+ int size)
+{
+ resource_size_t res_size = pci_rebar_size_to_bytes(size);
+ struct resource *res = dev->resource + resno;
+
+ if (!pci_resource_is_iov(resno)) {
+ res->end = res->start + res_size - 1;
+ } else {
+ res->end = res->start +
+ res_size * pci_sriov_get_totalvfs(dev) - 1;
+ pci_iov_resource_set_size(dev, resno, res_size);
+ }
+}
+
int pci_resize_resource(struct pci_dev *dev, int resno, int size)
{
struct resource *res = dev->resource + resno;
struct pci_host_bridge *host;
int old, ret;
u32 sizes;
- u16 cmd;
/* Check if we must preserve the firmware's resource assignment */
host = pci_find_host_bridge(dev->bus);
@@ -442,8 +469,7 @@ int pci_resize_resource(struct pci_dev *dev, int resno, int size)
if (!(res->flags & IORESOURCE_UNSET))
return -EBUSY;
- pci_read_config_word(dev, PCI_COMMAND, &cmd);
- if (cmd & PCI_COMMAND_MEMORY)
+ if (pci_resize_is_memory_decoding_enabled(dev, resno))
return -EBUSY;
sizes = pci_rebar_get_possible_sizes(dev, resno);
@@ -461,7 +487,7 @@ int pci_resize_resource(struct pci_dev *dev, int resno, int size)
if (ret)
return ret;
- res->end = res->start + pci_rebar_size_to_bytes(size) - 1;
+ pci_resize_resource_set_size(dev, resno, size);
/* Check if the new config works by trying to assign everything. */
if (dev->bus->self) {
@@ -473,7 +499,7 @@ int pci_resize_resource(struct pci_dev *dev, int resno, int size)
error_resize:
pci_rebar_set_size(dev, resno, old);
- res->end = res->start + pci_rebar_size_to_bytes(old) - 1;
+ pci_resize_resource_set_size(dev, resno, old);
return ret;
}
EXPORT_SYMBOL(pci_resize_resource);
--
2.47.0
More information about the dri-devel
mailing list