[net-next 08/10] net/mlx5: Add Vendor Specific Capability access gateway

Saeed Mahameed
2018-08-01T23:49:09Z

From: Alex Vesker <valex@mellanox.com>

The Vendor Specific Capability (VSC) is used to activate a gateway
interfacing with the device. The gateway is used to read or write
device configurations, which are organized in different domains (spaces).
A configuration access may result in multiple actions, reads, writes.

Example usages are accessing the Crspace domain to read the crspace or
locking a device semaphore using the Semaphore domain.

Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
---
.../net/ethernet/mellanox/mlx5/core/Makefile | 2 +-
.../net/ethernet/mellanox/mlx5/core/health.c | 2 +
.../ethernet/mellanox/mlx5/core/lib/pci_vsc.c | 320 ++++++++++++++++++
.../ethernet/mellanox/mlx5/core/lib/pci_vsc.h | 56 +++
include/linux/mlx5/driver.h | 1 +
5 files changed, 380 insertions(+), 1 deletion(-)
create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.c
create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.h

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Makefile b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
index 0be5bf93f33b..15f6916efe1b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/Makefile
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
@@ -6,7 +6,7 @@ mlx5_core-y := main.o cmd.o debugfs.o fw.o eq.o uar.o pagealloc.o \
health.o mcg.o cq.o srq.o alloc.o qp.o port.o mr.o pd.o \
mad.o transobj.o vport.o sriov.o fs_cmd.o fs_core.o \
fs_counters.o rl.o lag.o dev.o wq.o lib/gid.o lib/clock.o \
- diag/fs_tracepoint.o diag/fw_tracer.o devlink.o
+ lib/pci_vsc.o diag/fs_tracepoint.o diag/fw_tracer.o devlink.o

mlx5_core-$(CONFIG_MLX5_ACCEL) += accel/ipsec.o accel/tls.o

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/health.c b/drivers/net/ethernet/mellanox/mlx5/core/health.c
index d39b0b7011b2..db9e39fdc33e 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/health.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/health.c
@@ -38,6 +38,7 @@
#include <linux/mlx5/driver.h>
#include <linux/mlx5/cmd.h>
#include "mlx5_core.h"
+#include "lib/pci_vsc.h"

enum {
MLX5_HEALTH_POLL_INTERVAL = 2 * HZ,
@@ -388,6 +389,7 @@ int mlx5_health_init(struct mlx5_core_dev *dev)
spin_lock_init(&health->wq_lock);
INIT_WORK(&health->work, health_care);
INIT_DELAYED_WORK(&health->recover_work, health_recover);
+ mlx5_vsc_init(dev);

return 0;
}
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.c
new file mode 100644
index 000000000000..cfc2eebbf7c5
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.c
@@ -0,0 +1,320 @@
+/*
+ * Copyright (c) 2018, Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/pci.h>
+#include "mlx5_core.h"
+#include "pci_vsc.h"
+
+#define MLX5_EXTRACT_C(source, offset, size) \
+ ((((unsigned)(source)) >> (offset)) & MLX5_ONES32(size))
+#define MLX5_EXTRACT(src, start, len) \
+ (((len) == 32) ? (src) : MLX5_EXTRACT_C(src, start, len))
+#define MLX5_ONES32(size) \
+ ((size) ? (0xffffffff >> (32 - (size))) : 0)
+#define MLX5_MASK32(offset, size) \
+ (MLX5_ONES32(size) << (offset))
+#define MLX5_MERGE_C(rsrc1, rsrc2, start, len) \
+ ((((rsrc2) << (start)) & (MLX5_MASK32((start), (len)))) | \
+ ((rsrc1) & (~MLX5_MASK32((start), (len)))))
+#define MLX5_MERGE(rsrc1, rsrc2, start, len) \
+ (((len) == 32) ? (rsrc2) : MLX5_MERGE_C(rsrc1, rsrc2, start, len))
+
+#define VSC_MAX_RETRIES 2048
+
+enum {
+ MLX5_VSC_UNLOCK,
+ MLX5_VSC_LOCK,
+};
+
+enum {
+ VSC_CTRL_OFFSET = 0x4,
+ VSC_COUNTER_OFFSET = 0x8,
+ VSC_SEMAPHORE_OFFSET = 0xc,
+ VSC_ADDR_OFFSET = 0x10,
+ VSC_DATA_OFFSET = 0x14,
+
+ VSC_FLAG_BIT_OFFS = 31,
+ VSC_FLAG_BIT_LEN = 1,
+
+ VSC_SYND_BIT_OFFS = 30,
+ VSC_SYND_BIT_LEN = 1,
+
+ VSC_ADDR_BIT_OFFS = 0,
+ VSC_ADDR_BIT_LEN = 30,
+
+ VSC_SPACE_BIT_OFFS = 0,
+ VSC_SPACE_BIT_LEN = 16,
+
+ VSC_SIZE_VLD_BIT_OFFS = 28,
+ VSC_SIZE_VLD_BIT_LEN = 1,
+
+ VSC_STATUS_BIT_OFFS = 29,
+ VSC_STATUS_BIT_LEN = 3,
+};
+
+int mlx5_vsc_init(struct mlx5_core_dev *dev)
+{
+ struct mlx5_priv *priv = &dev->priv;
+
+ priv->health.vsc_addr = pci_find_capability(dev->pdev,
+ PCI_CAP_ID_VNDR);
+ if (!priv->health.vsc_addr)
+ mlx5_core_warn(dev, "Failed to get valid vendor specific ID\n");
+
+ return 0;
+}
+
+int mlx5_vsc_gw_lock(struct mlx5_core_dev *dev)
+{
+ struct mlx5_priv *priv = &dev->priv;
+ u32 counter = 0;
+ int retries = 0;
+ u32 lock_val;
+ int ret;
+
+ do {
+ if (retries > VSC_MAX_RETRIES)
+ return -EBUSY;
+
+ /* Check if semaphore is already locked */
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_SEMAPHORE_OFFSET,
+ &lock_val);
+ if (ret)
+ return ret;
+
+ if (lock_val) {
+ retries++;
+ usleep_range(1000, 2000);
+ continue;
+ }
+
+ /*
+ * Read and write counter value, if written value is
+ * the same, semaphore was acquired successfully.
+ */
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_COUNTER_OFFSET,
+ &counter);
+ if (ret)
+ return ret;
+
+ ret = pci_write_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_SEMAPHORE_OFFSET,
+ counter);
+ if (ret)
+ return ret;
+
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_SEMAPHORE_OFFSET,
+ &lock_val);
+ if (ret)
+ return ret;
+
+ retries++;
+ } while (counter != lock_val);
+
+ return 0;
+}
+
+int mlx5_vsc_gw_unlock(struct mlx5_core_dev *dev)
+{
+ struct mlx5_priv *priv = &dev->priv;
+ int ret;
+
+ ret = pci_write_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_SEMAPHORE_OFFSET,
+ MLX5_VSC_UNLOCK);
+ return ret;
+}
+
+int mlx5_vsc_gw_set_space(struct mlx5_core_dev *dev, u16 space,
+ u32 *ret_space_size)
+{
+ struct mlx5_priv *priv = &dev->priv;
+ int ret;
+ u32 val;
+
+ if (!mlx5_vsc_accessible(dev))
+ return -EINVAL;
+
+ if (ret_space_size)
+ *ret_space_size = 0;
+
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_CTRL_OFFSET,
+ &val);
+ if (ret)
+ goto out;
+
+ val = MLX5_MERGE(val, space, VSC_SPACE_BIT_OFFS, VSC_SPACE_BIT_LEN);
+ ret = pci_write_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_CTRL_OFFSET,
+ val);
+ if (ret)
+ goto out;
+
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_CTRL_OFFSET,
+ &val);
+ if (ret)
+ goto out;
+
+ if (MLX5_EXTRACT(val, VSC_STATUS_BIT_OFFS, VSC_STATUS_BIT_LEN) == 0)
+ return -EINVAL;
+
+ /* Get space max address if indicated by size valid bit */
+ if (ret_space_size &&
+ MLX5_EXTRACT(val, VSC_SIZE_VLD_BIT_OFFS, VSC_SIZE_VLD_BIT_LEN)) {
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_ADDR_OFFSET,
+ &val);
+ if (ret) {
+ mlx5_core_warn(dev, "Failed to get max space size\n");
+ goto out;
+ }
+ *ret_space_size = MLX5_EXTRACT(val, VSC_ADDR_BIT_OFFS,
+ VSC_ADDR_BIT_LEN);
+ }
+ return 0;
+
+out:
+ return ret;
+}
+
+static int mlx5_vsc_wait_on_flag(struct mlx5_core_dev *dev, u8 expected_val)
+{
+ struct mlx5_priv *priv = &dev->priv;
+ int retries = 0;
+ u32 flag;
+ int ret;
+
+ do {
+ if (retries > VSC_MAX_RETRIES)
+ return -EBUSY;
+
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_ADDR_OFFSET,
+ &flag);
+ flag = MLX5_EXTRACT(flag, VSC_FLAG_BIT_OFFS, VSC_FLAG_BIT_LEN);
+ retries++;
+
+ if ((retries & 0xf) == 0)
+ usleep_range(1000, 2000);
+
+ } while (flag != expected_val);
+
+ return 0;
+}
+
+static int mlx5_vsc_gw_read(struct mlx5_core_dev *dev, unsigned int address,
+ u32 *data)
+{
+ struct mlx5_priv *priv = &dev->priv;
+ int ret;
+
+ if (MLX5_EXTRACT(address, VSC_SYND_BIT_OFFS,
+ VSC_FLAG_BIT_LEN + VSC_SYND_BIT_LEN))
+ return -EINVAL;
+
+ ret = pci_write_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_ADDR_OFFSET,
+ address);
+ if (ret)
+ goto out;
+
+ ret = mlx5_vsc_wait_on_flag(dev, 1);
+ if (ret)
+ goto out;
+
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_DATA_OFFSET,
+ data);
+out:
+ return ret;
+}
+
+static int mlx5_vsc_gw_read_fast(struct mlx5_core_dev *dev,
+ unsigned int read_addr,
+ unsigned int *next_read_addr,
+ u32 *data)
+{
+ struct mlx5_priv *priv = &dev->priv;
+ int ret;
+
+ ret = mlx5_vsc_gw_read(dev, read_addr, data);
+ if (ret)
+ goto out;
+
+ ret = pci_read_config_dword(dev->pdev,
+ priv->health.vsc_addr +
+ VSC_ADDR_OFFSET,
+ next_read_addr);
+ if (ret)
+ goto out;
+
+ *next_read_addr = MLX5_EXTRACT(*next_read_addr, VSC_ADDR_BIT_OFFS,
+ VSC_ADDR_BIT_LEN);
+
+ if (*next_read_addr <= read_addr)
+ ret = EINVAL;
+out:
+ return ret;
+}
+
+int mlx5_vsc_gw_read_block_fast(struct mlx5_core_dev *dev, u32 *data,
+ int length)
+{
+ unsigned int next_read_addr = 0;
+ unsigned int read_addr = 0;
+
+ while (read_addr < length) {
+ if (mlx5_vsc_gw_read_fast(dev, read_addr, &next_read_addr,
+ &data[(read_addr >> 2)]))
+ return read_addr;
+
+ read_addr = next_read_addr;
+ }
+ return length;
+}
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.h b/drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.h
new file mode 100644
index 000000000000..af10bce44692
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/pci_vsc.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2018, Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef __MLX5_PCI_VSC_H__
+#define __MLX5_PCI_VSC_H__
+
+enum {
+ MLX5_VSC_SPACE_SCAN_CRSPACE = 0x7,
+};
+
+int mlx5_vsc_init(struct mlx5_core_dev *dev);
+void mlx5_vsc_cleanup(struct mlx5_core_dev *dev);
+int mlx5_vsc_gw_lock(struct mlx5_core_dev *dev);
+int mlx5_vsc_gw_unlock(struct mlx5_core_dev *dev);
+int mlx5_vsc_gw_set_space(struct mlx5_core_dev *dev, u16 space,
+ u32 *ret_space_size);
+int mlx5_vsc_gw_read_block_fast(struct mlx5_core_dev *dev, u32 *data,
+ int length);
+
+static inline bool mlx5_vsc_accessible(struct mlx5_core_dev *dev)
+{
+ struct mlx5_priv *priv = &dev->priv;
+
+ return (!!priv->health.vsc_addr);
+}
+
+#endif /* __MLX5_PCI_VSC_H__ */
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 54f385cc8811..6690875b368b 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -541,6 +541,7 @@ struct mlx5_core_health {
unsigned long flags;
struct work_struct work;
struct delayed_work recover_work;
+ u32 vsc_addr;
};

struct mlx5_qp_table {
--
2.17.0