Merge tag 'mlx5-4kuar-for-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux

Saeed Mahameed says:

====================
mlx5 4K UAR

The following series of patches optimizes the usage of the UAR area which is
contained within the BAR 0-1. Previous versions of the firmware and the driver
assumed each system page contains a single UAR. This patch set will query the
firmware for a new capability that if published, means that the firmware can
support UARs of fixed 4K regardless of system page size. In the case of
powerpc, where page size equals 64KB, this means we can utilize 16 UARs per
system page. Since user space processes by default consume eight UARs per
context this means that with this change a process will need a single system
page to fulfill that requirement and in fact make use of more UARs which is
better in terms of performance.

In addition to optimizing user-space processes, we introduce an allocator
that can be used by kernel consumers to allocate blue flame registers
(which are areas within a UAR that are used to write doorbells). This provides
further optimization on using the UAR area since the Ethernet driver makes
use of a single blue flame register per system page and now it will use two
blue flame registers per 4K.

The series also makes changes to naming conventions and now the terms used in
the driver code match the terms used in the PRM (programmers reference manual).
Thus, what used to be called UUAR (micro UAR) is now called BFREG (blue flame
register).

In order to support compatibility between different versions of
library/driver/firmware, the library has now means to notify the kernel driver
that it supports the new scheme and the kernel can notify the library if it
supports this extension. So mixed versions of libraries can run concurrently
without any issues.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 68 insertions, 54 deletions

diff --git a/include/linux/mlx5/cq.h b/include/linux/mlx5/cq.h
index 7c3c0d3aca37..95898847c7d4 100644
--- a/include/linux/mlx5/cq.h
+++ b/include/linux/mlx5/cq.h
@@ -42,13 +42,13 @@ struct mlx5_core_cq {
 	int			cqe_sz;
 	__be32		       *set_ci_db;
 	__be32		       *arm_db;
+	struct mlx5_uars_page  *uar;
 	atomic_t		refcount;
 	struct completion	free;
 	unsigned		vector;
 	unsigned int		irqn;
 	void (*comp)		(struct mlx5_core_cq *);
 	void (*event)		(struct mlx5_core_cq *, enum mlx5_event);
-	struct mlx5_uar	       *uar;
 	u32			cons_index;
 	unsigned		arm_sn;
 	struct mlx5_rsc_debug	*dbg;
@@ -144,7 +144,6 @@ enum {
 
 static inline void mlx5_cq_arm(struct mlx5_core_cq *cq, u32 cmd,
 			       void __iomem *uar_page,
-			       spinlock_t *doorbell_lock,
 			       u32 cons_index)
 {
 	__be32 doorbell[2];
@@ -164,7 +163,7 @@ static inline void mlx5_cq_arm(struct mlx5_core_cq *cq, u32 cmd,
 	doorbell[0] = cpu_to_be32(sn << 28 | cmd | ci);
 	doorbell[1] = cpu_to_be32(cq->cqn);
 
-	mlx5_write64(doorbell, uar_page + MLX5_CQ_DOORBELL, doorbell_lock);
+	mlx5_write64(doorbell, uar_page + MLX5_CQ_DOORBELL, NULL);
 }
 
 int mlx5_init_cq_table(struct mlx5_core_dev *dev);
diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 7a79a20c54d2..7c5265db02a9 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -212,10 +212,20 @@ enum {
 };
 
 enum {
-	MLX5_BF_REGS_PER_PAGE		= 4,
-	MLX5_MAX_UAR_PAGES		= 1 << 8,
-	MLX5_NON_FP_BF_REGS_PER_PAGE	= 2,
-	MLX5_MAX_UUARS	= MLX5_MAX_UAR_PAGES * MLX5_NON_FP_BF_REGS_PER_PAGE,
+	MLX5_ADAPTER_PAGE_SHIFT		= 12,
+	MLX5_ADAPTER_PAGE_SIZE		= 1 << MLX5_ADAPTER_PAGE_SHIFT,
+};
+
+enum {
+	MLX5_BFREGS_PER_UAR		= 4,
+	MLX5_MAX_UARS			= 1 << 8,
+	MLX5_NON_FP_BFREGS_PER_UAR	= 2,
+	MLX5_FP_BFREGS_PER_UAR		= MLX5_BFREGS_PER_UAR -
+					  MLX5_NON_FP_BFREGS_PER_UAR,
+	MLX5_MAX_BFREGS			= MLX5_MAX_UARS *
+					  MLX5_NON_FP_BFREGS_PER_UAR,
+	MLX5_UARS_IN_PAGE		= PAGE_SIZE / MLX5_ADAPTER_PAGE_SIZE,
+	MLX5_NON_FP_BFREGS_IN_PAGE	= MLX5_NON_FP_BFREGS_PER_UAR * MLX5_UARS_IN_PAGE,
 };
 
 enum {
@@ -389,11 +399,6 @@ enum {
 };
 
 enum {
-	MLX5_ADAPTER_PAGE_SHIFT		= 12,
-	MLX5_ADAPTER_PAGE_SIZE		= 1 << MLX5_ADAPTER_PAGE_SHIFT,
-};
-
-enum {
 	MLX5_CAP_OFF_CMDIF_CSUM		= 46,
 };
 
diff --git a/include/linux/mlx5/doorbell.h b/include/linux/mlx5/doorbell.h
index afc78a3f4462..0787de28f2fc 100644
--- a/include/linux/mlx5/doorbell.h
+++ b/include/linux/mlx5/doorbell.h
@@ -68,10 +68,12 @@ static inline void mlx5_write64(__be32 val[2], void __iomem *dest,
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(doorbell_lock, flags);
+	if (doorbell_lock)
+		spin_lock_irqsave(doorbell_lock, flags);
 	__raw_writel((__force u32) val[0], dest);
 	__raw_writel((__force u32) val[1], dest + 4);
-	spin_unlock_irqrestore(doorbell_lock, flags);
+	if (doorbell_lock)
+		spin_unlock_irqrestore(doorbell_lock, flags);
 }
 
 #endif
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index cdd2bd62f86d..3a309f6a4a15 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -187,36 +187,18 @@ enum mlx5_eq_type {
 #endif
 };
 
-struct mlx5_uuar_info {
-	struct mlx5_uar	       *uars;
-	int			num_uars;
-	int			num_low_latency_uuars;
-	unsigned long	       *bitmap;
+struct mlx5_bfreg_info {
+	u32		       *sys_pages;
+	int			num_low_latency_bfregs;
 	unsigned int	       *count;
-	struct mlx5_bf	       *bfs;
 
 	/*
-	 * protect uuar allocation data structs
+	 * protect bfreg allocation data structs
 	 */
 	struct mutex		lock;
 	u32			ver;
-};
-
-struct mlx5_bf {
-	void __iomem	       *reg;
-	void __iomem	       *regreg;
-	int			buf_size;
-	struct mlx5_uar	       *uar;
-	unsigned long		offset;
-	int			need_lock;
-	/* protect blue flame buffer selection when needed
-	 */
-	spinlock_t		lock;
-
-	/* serialize 64 bit writes when done as two 32 bit accesses
-	 */
-	spinlock_t		lock32;
-	int			uuarn;
+	bool			lib_uar_4k;
+	u32			num_sys_pages;
 };
 
 struct mlx5_cmd_first {
@@ -451,14 +433,38 @@ struct mlx5_eq_table {
 	spinlock_t		lock;
 };
 
-struct mlx5_uar {
-	u32			index;
-	struct list_head	bf_list;
-	unsigned		free_bf_bmap;
-	void __iomem	       *bf_map;
+struct mlx5_uars_page {
 	void __iomem	       *map;
+	bool			wc;
+	u32			index;
+	struct list_head	list;
+	unsigned int		bfregs;
+	unsigned long	       *reg_bitmap; /* for non fast path bf regs */
+	unsigned long	       *fp_bitmap;
+	unsigned int		reg_avail;
+	unsigned int		fp_avail;
+	struct kref		ref_count;
+	struct mlx5_core_dev   *mdev;
 };
 
+struct mlx5_bfreg_head {
+	/* protect blue flame registers allocations */
+	struct mutex		lock;
+	struct list_head	list;
+};
+
+struct mlx5_bfreg_data {
+	struct mlx5_bfreg_head	reg_head;
+	struct mlx5_bfreg_head	wc_head;
+};
+
+struct mlx5_sq_bfreg {
+	void __iomem	       *map;
+	struct mlx5_uars_page  *up;
+	bool			wc;
+	u32			index;
+	unsigned int		offset;
+};
 
 struct mlx5_core_health {
 	struct health_buffer __iomem   *health;
@@ -578,8 +584,6 @@ struct mlx5_priv {
 	struct mlx5_eq_table	eq_table;
 	struct msix_entry	*msix_arr;
 	struct mlx5_irq_info	*irq_info;
-	struct mlx5_uuar_info	uuari;
-	MLX5_DECLARE_DOORBELL_LOCK(cq_uar_lock);
 
 	/* pages stuff */
 	struct workqueue_struct *pg_wq;
@@ -644,6 +648,8 @@ struct mlx5_priv {
 	void		       *pfault_ctx;
 	struct srcu_struct      pfault_srcu;
 #endif
+	struct mlx5_bfreg_data		bfregs;
+	struct mlx5_uars_page	       *uar;
 };
 
 enum mlx5_device_state {
@@ -712,7 +718,6 @@ struct mlx5_td {
 };
 
 struct mlx5e_resources {
-	struct mlx5_uar            cq_uar;
 	u32                        pdn;
 	struct mlx5_td             td;
 	struct mlx5_core_mkey      mkey;
@@ -902,11 +907,6 @@ void mlx5_cmd_mbox_status(void *out, u8 *status, u32 *syndrome);
 int mlx5_core_get_caps(struct mlx5_core_dev *dev, enum mlx5_cap_type cap_type);
 int mlx5_cmd_alloc_uar(struct mlx5_core_dev *dev, u32 *uarn);
 int mlx5_cmd_free_uar(struct mlx5_core_dev *dev, u32 uarn);
-int mlx5_alloc_uuars(struct mlx5_core_dev *dev, struct mlx5_uuar_info *uuari);
-int mlx5_free_uuars(struct mlx5_core_dev *dev, struct mlx5_uuar_info *uuari);
-int mlx5_alloc_map_uar(struct mlx5_core_dev *mdev, struct mlx5_uar *uar,
-		       bool map_wc);
-void mlx5_unmap_free_uar(struct mlx5_core_dev *mdev, struct mlx5_uar *uar);
 void mlx5_health_cleanup(struct mlx5_core_dev *dev);
 int mlx5_health_init(struct mlx5_core_dev *dev);
 void mlx5_start_health_poll(struct mlx5_core_dev *dev);
@@ -972,7 +972,7 @@ void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, u64 vec);
 void mlx5_cq_event(struct mlx5_core_dev *dev, u32 cqn, int event_type);
 int mlx5_create_map_eq(struct mlx5_core_dev *dev, struct mlx5_eq *eq, u8 vecidx,
 		       int nent, u64 mask, const char *name,
-		       struct mlx5_uar *uar, enum mlx5_eq_type type);
+		       enum mlx5_eq_type type);
 int mlx5_destroy_unmap_eq(struct mlx5_core_dev *dev, struct mlx5_eq *eq);
 int mlx5_start_eqs(struct mlx5_core_dev *dev);
 int mlx5_stop_eqs(struct mlx5_core_dev *dev);
@@ -1021,6 +1021,9 @@ void mlx5_cleanup_rl_table(struct mlx5_core_dev *dev);
 int mlx5_rl_add_rate(struct mlx5_core_dev *dev, u32 rate, u16 *index);
 void mlx5_rl_remove_rate(struct mlx5_core_dev *dev, u32 rate);
 bool mlx5_rl_is_in_range(struct mlx5_core_dev *dev, u32 rate);
+int mlx5_alloc_bfreg(struct mlx5_core_dev *mdev, struct mlx5_sq_bfreg *bfreg,
+		     bool map_wc, bool fast_path);
+void mlx5_free_bfreg(struct mlx5_core_dev *mdev, struct mlx5_sq_bfreg *bfreg);
 
 static inline int fw_initializing(struct mlx5_core_dev *dev)
 {
@@ -1080,6 +1083,8 @@ int mlx5_cmd_create_vport_lag(struct mlx5_core_dev *dev);
 int mlx5_cmd_destroy_vport_lag(struct mlx5_core_dev *dev);
 bool mlx5_lag_is_active(struct mlx5_core_dev *dev);
 struct net_device *mlx5_lag_get_roce_netdev(struct mlx5_core_dev *dev);
+struct mlx5_uars_page *mlx5_get_uars_page(struct mlx5_core_dev *mdev);
+void mlx5_put_uars_page(struct mlx5_core_dev *mdev, struct mlx5_uars_page *up);
 
 struct mlx5_profile {
 	u64	mask;
diff --git a/include/linux/mlx5/mlx5_ifc.h b/include/linux/mlx5/mlx5_ifc.h
index d0f090884617..37327f6ba9cb 100644
--- a/include/linux/mlx5/mlx5_ifc.h
+++ b/include/linux/mlx5/mlx5_ifc.h
@@ -905,7 +905,8 @@ struct mlx5_ifc_cmd_hca_cap_bits {
 	u8         uc[0x1];
 	u8         rc[0x1];
 
-	u8         reserved_at_240[0xa];
+	u8         uar_4k[0x1];
+	u8         reserved_at_241[0x9];
 	u8         uar_sz[0x6];
 	u8         reserved_at_250[0x8];
 	u8         log_pg_sz[0x8];
@@ -997,7 +998,9 @@ struct mlx5_ifc_cmd_hca_cap_bits {
 	u8         device_frequency_mhz[0x20];
 	u8         device_frequency_khz[0x20];
 
-	u8         reserved_at_500[0x80];
+	u8         reserved_at_500[0x20];
+	u8	   num_of_uars_per_page[0x20];
+	u8         reserved_at_540[0x40];
 
 	u8         reserved_at_580[0x3f];
 	u8         cqe_compression[0x1];