AMD NTB support two features: flush pending requests and wakeup
opposite side from low power state. This patch add two interface
to support these features.
Signed-off-by: Xiangliang Yu <[email protected]>
---
drivers/ntb/hw/amd/ntb_hw_amd.c | 16 ++++++++++++++++
drivers/ntb/hw/amd/ntb_hw_amd.h | 2 ++
include/linux/ntb.h | 33 +++++++++++++++++++++++++++++++++
3 files changed, 51 insertions(+)
diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.c b/drivers/ntb/hw/amd/ntb_hw_amd.c
index 931dcdc..e0ff663 100644
--- a/drivers/ntb/hw/amd/ntb_hw_amd.c
+++ b/drivers/ntb/hw/amd/ntb_hw_amd.c
@@ -93,6 +93,8 @@ static const struct ntb_dev_ops amd_ntb_ops = {
.peer_spad_addr = amd_ntb_peer_spad_addr,
.peer_spad_read = amd_ntb_peer_spad_read,
.peer_spad_write = amd_ntb_peer_spad_write,
+ .flush_req = amd_ntb_flush_req,
+ .peer_wakeup = amd_ntb_wakeup_peer_side,
};
static int ndev_mw_to_bar(struct amd_ntb_dev *ndev, int idx)
@@ -501,6 +503,13 @@ static int amd_flush_peer_requests(struct amd_ntb_dev *ndev)
return 0;
}
+static int amd_ntb_flush_req(struct ntb_dev *ntb)
+{
+ struct amd_ntb_dev *ndev = ntb_ndev(ntb);
+
+ return amd_flush_peer_requests(ndev);
+}
+
/*
* wake up the peer side
*/
@@ -522,6 +531,13 @@ static int amd_wakeup_peer_side(struct amd_ntb_dev *ndev)
return 0;
}
+static int amd_ntb_wakeup_peer_side(struct ntb_dev *ntb)
+{
+ struct amd_ntb_dev *ndev = ntb_ndev(ntb);
+
+ return amd_wakeup_peer_side(ndev);
+}
+
static void amd_handle_event(struct amd_ntb_dev *ndev, int vec)
{
u32 status;
diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.h b/drivers/ntb/hw/amd/ntb_hw_amd.h
index c3085c8..2d9b5be 100644
--- a/drivers/ntb/hw/amd/ntb_hw_amd.h
+++ b/drivers/ntb/hw/amd/ntb_hw_amd.h
@@ -263,4 +263,6 @@ static int amd_ntb_peer_spad_addr(struct ntb_dev *ntb, int idx,
phys_addr_t *spad_addr);
static u32 amd_ntb_peer_spad_read(struct ntb_dev *ntb, int idx);
static int amd_ntb_peer_spad_write(struct ntb_dev *ntb, int idx, u32 val);
+static int amd_ntb_flush_req(struct ntb_dev *ntb);
+static int amd_ntb_wakeup_peer_side(struct ntb_dev *ntb);
#endif
diff --git a/include/linux/ntb.h b/include/linux/ntb.h
index f798e2a..9149138 100644
--- a/include/linux/ntb.h
+++ b/include/linux/ntb.h
@@ -210,6 +210,8 @@ static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops)
* @peer_spad_addr: See ntb_peer_spad_addr().
* @peer_spad_read: See ntb_peer_spad_read().
* @peer_spad_write: See ntb_peer_spad_write().
+ * @flush_req: See ntb_flush_requests().
+ * @peer_wakeup: See ntb_wakeup_peer_side().
*/
struct ntb_dev_ops {
int (*mw_count)(struct ntb_dev *ntb);
@@ -259,6 +261,9 @@ struct ntb_dev_ops {
phys_addr_t *spad_addr);
u32 (*peer_spad_read)(struct ntb_dev *ntb, int idx);
int (*peer_spad_write)(struct ntb_dev *ntb, int idx, u32 val);
+
+ int (*flush_req)(struct ntb_dev *ntb);
+ int (*peer_wakeup)(struct ntb_dev *ntb);
};
static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops)
@@ -980,4 +985,32 @@ static inline int ntb_peer_spad_write(struct ntb_dev *ntb, int idx, u32 val)
return ntb->ops->peer_spad_write(ntb, idx, val);
}
+/**
+ * ntb_flush_requests() - flush all pending requests
+ * @ntb: NTB device context.
+ *
+ * For some usage, one side of NTB need to first make sure that all previous
+ * requests have been completed and then execute next step such as power down,
+ * or device removed.
+ *
+ * Return: Zero on success, otherwise an error number.
+ */
+static inline int ntb_flush_requests(struct ntb_dev *ntb)
+{
+ return ntb->ops->flush_req(ntb);
+}
+
+/**
+ * ntb_wakeup_peer_side() - wakeup peer side of NTB.
+ * @ntb: NTB device context.
+ *
+ * Provide a mechanism that wakeup opposite side from low power state.
+ *
+ * Return: Zero on success, otherwise an error number.
+ */
+static inline int ntb_wakeup_peer_side(struct ntb_dev *ntb)
+{
+ return ntb->ops->peer_wakeup(ntb);
+}
+
#endif
--
1.9.1
Hi Xiangliang,
[auto build test WARNING on v4.4-rc5]
[also build test WARNING on next-20151217]
url: https://github.com/0day-ci/linux/commits/Xiangliang-Yu/NTB-Add-AMD-PCI-Express-NTB-driver/20151217-113608
config: x86_64-randconfig-n0-12171710 (attached as .config)
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All warnings (new ones prefixed by >>):
drivers/ntb/hw/amd/ntb_hw_amd.c: In function 'amd_ntb_mw_set_trans':
drivers/ntb/hw/amd/ntb_hw_amd.c:189:6: warning: 'limit' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (reg_val != limit) {
^
drivers/ntb/hw/amd/ntb_hw_amd.c: In function 'amd_ntb_wakeup_peer_side':
>> drivers/ntb/hw/amd/ntb_hw_amd.c:526:6: warning: 'reg' may be used uninitialized in this function [-Wmaybe-uninitialized]
reg |= 0x1;
^
drivers/ntb/hw/amd/ntb_hw_amd.c:518:6: note: 'reg' was declared here
u32 reg;
^
vim +/reg +526 drivers/ntb/hw/amd/ntb_hw_amd.c
58a6d117 Xiangliang Yu 2015-12-17 510 return amd_flush_peer_requests(ndev);
58a6d117 Xiangliang Yu 2015-12-17 511 }
58a6d117 Xiangliang Yu 2015-12-17 512
a635755a Xiangliang Yu 2015-12-17 513 /*
a635755a Xiangliang Yu 2015-12-17 514 * wake up the peer side
a635755a Xiangliang Yu 2015-12-17 515 */
a635755a Xiangliang Yu 2015-12-17 516 static int amd_wakeup_peer_side(struct amd_ntb_dev *ndev)
a635755a Xiangliang Yu 2015-12-17 517 {
a635755a Xiangliang Yu 2015-12-17 518 u32 reg;
a635755a Xiangliang Yu 2015-12-17 519
a635755a Xiangliang Yu 2015-12-17 520 if (!amd_link_is_up(ndev)) {
a635755a Xiangliang Yu 2015-12-17 521 dev_warn(ndev_dev(ndev), "link is down.\n");
a635755a Xiangliang Yu 2015-12-17 522 return -EINVAL;
a635755a Xiangliang Yu 2015-12-17 523 }
a635755a Xiangliang Yu 2015-12-17 524
a635755a Xiangliang Yu 2015-12-17 525 NTB_READ_REG(PMSGTRIG);
a635755a Xiangliang Yu 2015-12-17 @526 reg |= 0x1;
a635755a Xiangliang Yu 2015-12-17 527 NTB_WRITE_REG(reg, PMSGTRIG);
a635755a Xiangliang Yu 2015-12-17 528
a635755a Xiangliang Yu 2015-12-17 529 wait_for_completion(&ndev->wakeup_cmpl);
a635755a Xiangliang Yu 2015-12-17 530
a635755a Xiangliang Yu 2015-12-17 531 return 0;
a635755a Xiangliang Yu 2015-12-17 532 }
a635755a Xiangliang Yu 2015-12-17 533
58a6d117 Xiangliang Yu 2015-12-17 534 static int amd_ntb_wakeup_peer_side(struct ntb_dev *ntb)
:::::: The code at line 526 was first introduced by commit
:::::: a635755a710138a6f505cc7e62693741786fb19e NTB: Add AMD PCI-Express NTB driver
:::::: TO: Xiangliang Yu <[email protected]>
:::::: CC: 0day robot <[email protected]>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation