net/mlx4_core: Set UAR page size to 4KB regardless of system page size

problem description:

The current code sets UAR page size equal to system page size.
The ConnectX-3 and ConnectX-3 Pro HWs require minimum 128 UAR pages.
The mlx4 kernel drivers are not loaded if there is less than 128 UAR pages.

solution:

Always set UAR page to 4KB. This allows more UAR pages if the OS
has PAGE_SIZE larger than 4KB. For example, PowerPC kernel use 64KB
system page size, with 4MB uar region, there are 4MB/2/64KB = 32
uars (half for uar, half for blueflame). This does not meet minimum 128
UAR pages requirement. With 4KB UAR page, there are 4MB/2/4KB = 512 uars
which meet the minimum requirement.

Note that only codes in mlx4_core that deal with firmware know that uar
page size is 4KB. Codes that deal with usr page in cq and qp context
(mlx4_ib, mlx4_en and part of mlx4_core) still have the same assumption
that uar page size equals to system page size.

Note that with this implementation, on 64KB system page size kernel, there
are 16 uars per system page but only one uars is used. The other 15
uars are ignored because of the above assumption.

Regarding SR-IOV, mlx4_core in hypervisor will set the uar page size
to 4KB and mlx4_core code in virtual OS will obtain the uar page size from
firmware.

Regarding backward compatibility in SR-IOV, if hypervisor has this new code,
the virtual OS must be updated. If hypervisor has old code, and the virtual
OS has this new code, the new code will be backward compatible with the
old code. If the uar size is big enough, this new code in VF continues to
work with 64 KB uar page size (on PowerPc kernel). If the uar size does not
meet 128 uars requirement, this new code not loaded in VF and print the same
error message as the old code in Hypervisor.

Signed-off-by: Huy Nguyen <huyn@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c
index bc5536f00b6cd4cc148f65b2c6131d7e627544eb..fd97534762b8dc7f83651a52e9398a3aa6e4944e 100644 (file)
--- a/drivers/infiniband/hw/mlx4/qp.c
+++ b/drivers/infiniband/hw/mlx4/qp.c
@@ -1681,9 +1681,12 @@ static int __mlx4_ib_modify_qp(struct ib_qp *ibqp,
        }
 
        if (qp->ibqp.uobject)
-               context->usr_page = cpu_to_be32(to_mucontext(ibqp->uobject->context)->uar.index);
+               context->usr_page = cpu_to_be32(
+                       mlx4_to_hw_uar_index(dev->dev,
+                                            to_mucontext(ibqp->uobject->context)->uar.index));
        else
-               context->usr_page = cpu_to_be32(dev->priv_uar.index);
+               context->usr_page = cpu_to_be32(
+                       mlx4_to_hw_uar_index(dev->dev, dev->priv_uar.index));
 
        if (attr_mask & IB_QP_DEST_QPN)
                context->remote_qpn = cpu_to_be32(attr->dest_qp_num);

diff --git a/drivers/net/ethernet/mellanox/mlx4/cq.c b/drivers/net/ethernet/mellanox/mlx4/cq.c
index 3348e646db705f41ff1cb3923d4d1533aea80e2d..a849da92f857e5c22cd1ec93158cecbff9c75d90 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/cq.c
+++ b/drivers/net/ethernet/mellanox/mlx4/cq.c
@@ -318,7 +318,9 @@ int mlx4_cq_alloc(struct mlx4_dev *dev, int nent,
        if (timestamp_en)
                cq_context->flags  |= cpu_to_be32(1 << 19);
 
-       cq_context->logsize_usrpage = cpu_to_be32((ilog2(nent) << 24) | uar->index);
+       cq_context->logsize_usrpage =
+               cpu_to_be32((ilog2(nent) << 24) |
+                           mlx4_to_hw_uar_index(dev, uar->index));
        cq_context->comp_eqn        = priv->eq_table.eq[MLX4_CQ_TO_EQ_VECTOR(vector)].eqn;
        cq_context->log_page_size   = mtt->page_shift - MLX4_ICM_PAGE_SHIFT;
 

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_resources.c b/drivers/net/ethernet/mellanox/mlx4/en_resources.c
index 12aab5a659d33e4c098a6b8bedf2d4014798e14c..02e925d6f7348d774fe70c4a91b5038d5a27ba35 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_resources.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_resources.c
@@ -58,7 +58,8 @@ void mlx4_en_fill_qp_context(struct mlx4_en_priv *priv, int size, int stride,
        } else {
                context->sq_size_stride = ilog2(TXBB_SIZE) - 4;
        }
-       context->usr_page = cpu_to_be32(mdev->priv_uar.index);
+       context->usr_page = cpu_to_be32(mlx4_to_hw_uar_index(mdev->dev,
+                                       mdev->priv_uar.index));
        context->local_qpn = cpu_to_be32(qpn);
        context->pri_path.ackto = 1 & 0x07;
        context->pri_path.sched_queue = 0x83 | (priv->port - 1) << 6;

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 4421bf5463f67159618c3a4c572b4e9ebc04dd7b..e0946ab22010f4d1c28373b33e8a9b8d334c764b 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -213,7 +213,9 @@ int mlx4_en_activate_tx_ring(struct mlx4_en_priv *priv,
        mlx4_en_fill_qp_context(priv, ring->size, ring->stride, 1, 0, ring->qpn,
                                ring->cqn, user_prio, &ring->context);
        if (ring->bf_alloced)
-               ring->context.usr_page = cpu_to_be32(ring->bf.uar->index);
+               ring->context.usr_page =
+                       cpu_to_be32(mlx4_to_hw_uar_index(mdev->dev,
+                                                        ring->bf.uar->index));
 
        err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, &ring->context,
                               &ring->qp, &ring->qp_state);

diff --git a/drivers/net/ethernet/mellanox/mlx4/eq.c b/drivers/net/ethernet/mellanox/mlx4/eq.c
index 4696053165f8ca192d5e8ccb21971d175d267ca7..f613977455e08340995baeb65763086e408479f3 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/eq.c
+++ b/drivers/net/ethernet/mellanox/mlx4/eq.c
@@ -940,9 +940,10 @@ static void __iomem *mlx4_get_eq_uar(struct mlx4_dev *dev, struct mlx4_eq *eq)
 
        if (!priv->eq_table.uar_map[index]) {
                priv->eq_table.uar_map[index] =
-                       ioremap(pci_resource_start(dev->persist->pdev, 2) +
-                               ((eq->eqn / 4) << PAGE_SHIFT),
-                               PAGE_SIZE);
+                       ioremap(
+                               pci_resource_start(dev->persist->pdev, 2) +
+                               ((eq->eqn / 4) << (dev->uar_page_shift)),
+                               (1 << (dev->uar_page_shift)));
                if (!priv->eq_table.uar_map[index]) {
                        mlx4_err(dev, "Couldn't map EQ doorbell for EQN 0x%06x\n",
                                 eq->eqn);

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index f1b6d219e445431c0dfe4f255b8abe9d3ec5f9b4..2cc3c626c3fea732d0862ff5f0ce520d442a6205 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -168,6 +168,20 @@ struct mlx4_port_config {
 
 static atomic_t pf_loading = ATOMIC_INIT(0);
 
+static inline void mlx4_set_num_reserved_uars(struct mlx4_dev *dev,
+                                             struct mlx4_dev_cap *dev_cap)
+{
+       /* The reserved_uars is calculated by system page size unit.
+        * Therefore, adjustment is added when the uar page size is less
+        * than the system page size
+        */
+       dev->caps.reserved_uars =
+               max_t(int,
+                     mlx4_get_num_reserved_uar(dev),
+                     dev_cap->reserved_uars /
+                       (1 << (PAGE_SHIFT - dev->uar_page_shift)));
+}
+
 int mlx4_check_port_params(struct mlx4_dev *dev,
                           enum mlx4_port_type *port_type)
 {
@@ -386,8 +400,6 @@ static int mlx4_dev_cap(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
        dev->caps.reserved_mtts      = dev_cap->reserved_mtts;
        dev->caps.reserved_mrws      = dev_cap->reserved_mrws;
 
-       /* The first 128 UARs are used for EQ doorbells */
-       dev->caps.reserved_uars      = max_t(int, 128, dev_cap->reserved_uars);
        dev->caps.reserved_pds       = dev_cap->reserved_pds;
        dev->caps.reserved_xrcds     = (dev->caps.flags & MLX4_DEV_CAP_FLAG_XRC) ?
                                        dev_cap->reserved_xrcds : 0;
@@ -405,6 +417,15 @@ static int mlx4_dev_cap(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
        dev->caps.max_gso_sz         = dev_cap->max_gso_sz;
        dev->caps.max_rss_tbl_sz     = dev_cap->max_rss_tbl_sz;
 
+       /* Save uar page shift */
+       if (!mlx4_is_slave(dev)) {
+               /* Virtual PCI function needs to determine UAR page size from
+                * firmware. Only master PCI function can set the uar page size
+                */
+               dev->uar_page_shift = DEFAULT_UAR_PAGE_SHIFT;
+               mlx4_set_num_reserved_uars(dev, dev_cap);
+       }
+
        if (dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_PHV_EN) {
                struct mlx4_init_hca_param hca_param;
 
@@ -815,16 +836,25 @@ static int mlx4_slave_cap(struct mlx4_dev *dev)
                return -ENODEV;
        }
 
-       /* slave gets uar page size from QUERY_HCA fw command */
-       dev->caps.uar_page_size = 1 << (hca_param.uar_page_sz + 12);
+       /* Set uar_page_shift for VF */
+       dev->uar_page_shift = hca_param.uar_page_sz + 12;
 
-       /* TODO: relax this assumption */
-       if (dev->caps.uar_page_size != PAGE_SIZE) {
-               mlx4_err(dev, "UAR size:%d != kernel PAGE_SIZE of %ld\n",
-                        dev->caps.uar_page_size, PAGE_SIZE);
-               return -ENODEV;
+       /* Make sure the master uar page size is valid */
+       if (dev->uar_page_shift > PAGE_SHIFT) {
+               mlx4_err(dev,
+                        "Invalid configuration: uar page size is larger than system page size\n");
+               return  -ENODEV;
        }
 
+       /* Set reserved_uars based on the uar_page_shift */
+       mlx4_set_num_reserved_uars(dev, &dev_cap);
+
+       /* Although uar page size in FW differs from system page size,
+        * upper software layers (mlx4_ib, mlx4_en and part of mlx4_core)
+        * still works with assumption that uar page size == system page size
+        */
+       dev->caps.uar_page_size = PAGE_SIZE;
+
        memset(&func_cap, 0, sizeof(func_cap));
        err = mlx4_QUERY_FUNC_CAP(dev, 0, &func_cap);
        if (err) {
@@ -2179,8 +2209,12 @@ static int mlx4_init_hca(struct mlx4_dev *dev)
 
                dev->caps.max_fmr_maps = (1 << (32 - ilog2(dev->caps.num_mpts))) - 1;
 
-               init_hca.log_uar_sz = ilog2(dev->caps.num_uars);
-               init_hca.uar_page_sz = PAGE_SHIFT - 12;
+               /* Always set UAR page size 4KB, set log_uar_sz accordingly */
+               init_hca.log_uar_sz = ilog2(dev->caps.num_uars) +
+                                     PAGE_SHIFT -
+                                     DEFAULT_UAR_PAGE_SHIFT;
+               init_hca.uar_page_sz = DEFAULT_UAR_PAGE_SHIFT - 12;
+
                init_hca.mw_enabled = 0;
                if (dev->caps.flags & MLX4_DEV_CAP_FLAG_MEM_WINDOW ||
                    dev->caps.bmme_flags & MLX4_BMME_FLAG_TYPE_2_WIN)

diff --git a/drivers/net/ethernet/mellanox/mlx4/pd.c b/drivers/net/ethernet/mellanox/mlx4/pd.c
index 609c59dc854e987a073e32cb4ff2c08736998edb..b3cc3ab63799462709a569cff08f6e4c5de59f43 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/pd.c
+++ b/drivers/net/ethernet/mellanox/mlx4/pd.c
@@ -269,9 +269,15 @@ EXPORT_SYMBOL_GPL(mlx4_bf_free);
 
 int mlx4_init_uar_table(struct mlx4_dev *dev)
 {
-       if (dev->caps.num_uars <= 128) {
-               mlx4_err(dev, "Only %d UAR pages (need more than 128)\n",
-                        dev->caps.num_uars);
+       int num_reserved_uar = mlx4_get_num_reserved_uar(dev);
+
+       mlx4_dbg(dev, "uar_page_shift = %d", dev->uar_page_shift);
+       mlx4_dbg(dev, "Effective reserved_uars=%d", dev->caps.reserved_uars);
+
+       if (dev->caps.num_uars <= num_reserved_uar) {
+               mlx4_err(
+                       dev, "Only %d UAR pages (need more than %d)\n",
+                       dev->caps.num_uars, num_reserved_uar);
                mlx4_err(dev, "Increase firmware log2_uar_bar_megabytes?\n");
                return -ENODEV;
        }

diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index 430a929f048b3d2f27d1e842f45e80f9e9e6347a..a0e8cc8dcc67dcc88e7d32ab47a8ef22af52c946 100644 (file)
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -44,6 +44,8 @@
 
 #include <linux/timecounter.h>
 
+#define DEFAULT_UAR_PAGE_SHIFT  12
+
 #define MAX_MSIX_P_PORT                17
 #define MAX_MSIX               64
 #define MIN_MSIX_P_PORT                5
@@ -856,6 +858,7 @@ struct mlx4_dev {
        u64                     regid_promisc_array[MLX4_MAX_PORTS + 1];
        u64                     regid_allmulti_array[MLX4_MAX_PORTS + 1];
        struct mlx4_vf_dev     *dev_vfs;
+       u8  uar_page_shift;
 };
 
 struct mlx4_clock_params {
@@ -1528,4 +1531,14 @@ int mlx4_ACCESS_PTYS_REG(struct mlx4_dev *dev,
 int mlx4_get_internal_clock_params(struct mlx4_dev *dev,
                                   struct mlx4_clock_params *params);
 
+static inline int mlx4_to_hw_uar_index(struct mlx4_dev *dev, int index)
+{
+       return (index << (PAGE_SHIFT - dev->uar_page_shift));
+}
+
+static inline int mlx4_get_num_reserved_uar(struct mlx4_dev *dev)
+{
+       /* The first 128 UARs are used for EQ doorbells */
+       return (128 >> (PAGE_SHIFT - dev->uar_page_shift));
+}
 #endif /* MLX4_DEVICE_H */