diff options
Diffstat (limited to 'drivers/net/ethernet/microchip/fdma/fdma_api.h')
| -rw-r--r-- | drivers/net/ethernet/microchip/fdma/fdma_api.h | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/net/ethernet/microchip/fdma/fdma_api.h b/drivers/net/ethernet/microchip/fdma/fdma_api.h new file mode 100644 index 000000000000..d91affe8bd98 --- /dev/null +++ b/drivers/net/ethernet/microchip/fdma/fdma_api.h @@ -0,0 +1,243 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ + +#ifndef _FDMA_API_H_ +#define _FDMA_API_H_ + +#include <linux/bits.h> +#include <linux/etherdevice.h> +#include <linux/types.h> + +/* This provides a common set of functions and data structures for interacting + * with the Frame DMA engine on multiple Microchip switchcores. + * + * Frame DMA DCB format: + * + * +---------------------------+ + * | Next Ptr | + * +---------------------------+ + * | Reserved | Info | + * +---------------------------+ + * | Data0 Ptr | + * +---------------------------+ + * | Reserved | Status0 | + * +---------------------------+ + * | Data1 Ptr | + * +---------------------------+ + * | Reserved | Status1 | + * +---------------------------+ + * | Data2 Ptr | + * +---------------------------+ + * | Reserved | Status2 | + * |-------------|-------------| + * | | + * | | + * | | + * | | + * | | + * |---------------------------| + * | Data14 Ptr | + * +-------------|-------------+ + * | Reserved | Status14 | + * +-------------|-------------+ + * + * The data pointers points to the actual frame data to be received or sent. The + * addresses of the data pointers can, as of writing, be either a: DMA address, + * physical address or mapped address. + * + */ + +#define FDMA_DCB_INFO_DATAL(x) ((x) & GENMASK(15, 0)) +#define FDMA_DCB_INFO_TOKEN BIT(17) +#define FDMA_DCB_INFO_INTR BIT(18) +#define FDMA_DCB_INFO_SW(x) (((x) << 24) & GENMASK(31, 24)) + +#define FDMA_DCB_STATUS_BLOCKL(x) ((x) & GENMASK(15, 0)) +#define FDMA_DCB_STATUS_SOF BIT(16) +#define FDMA_DCB_STATUS_EOF BIT(17) +#define FDMA_DCB_STATUS_INTR BIT(18) +#define FDMA_DCB_STATUS_DONE BIT(19) +#define FDMA_DCB_STATUS_BLOCKO(x) (((x) << 20) & GENMASK(31, 20)) +#define FDMA_DCB_INVALID_DATA 0x1 + +#define FDMA_DB_MAX 15 /* Max number of DB's on Sparx5 */ + +struct fdma; + +struct fdma_db { + u64 dataptr; + u64 status; +}; + +struct fdma_dcb { + u64 nextptr; + u64 info; + struct fdma_db db[FDMA_DB_MAX]; +}; + +struct fdma_ops { + /* User-provided callback to set the dataptr */ + int (*dataptr_cb)(struct fdma *fdma, int dcb_idx, int db_idx, u64 *ptr); + /* User-provided callback to set the nextptr */ + int (*nextptr_cb)(struct fdma *fdma, int dcb_idx, u64 *ptr); +}; + +struct fdma { + void *priv; + + /* Virtual addresses */ + struct fdma_dcb *dcbs; + struct fdma_dcb *last_dcb; + + /* DMA address */ + dma_addr_t dma; + + /* Size of DCB + DB memory */ + int size; + + /* Indexes used to access the next-to-be-used DCB or DB */ + int db_index; + int dcb_index; + + /* Number of DCB's and DB's */ + u32 n_dcbs; + u32 n_dbs; + + /* Size of DB's */ + u32 db_size; + + /* Channel id this FDMA object operates on */ + u32 channel_id; + + struct fdma_ops ops; +}; + +/* Advance the DCB index and wrap if required. */ +static inline void fdma_dcb_advance(struct fdma *fdma) +{ + fdma->dcb_index++; + if (fdma->dcb_index >= fdma->n_dcbs) + fdma->dcb_index = 0; +} + +/* Advance the DB index. */ +static inline void fdma_db_advance(struct fdma *fdma) +{ + fdma->db_index++; +} + +/* Reset the db index to zero. */ +static inline void fdma_db_reset(struct fdma *fdma) +{ + fdma->db_index = 0; +} + +/* Check if a DCB can be reused in case of multiple DB's per DCB. */ +static inline bool fdma_dcb_is_reusable(struct fdma *fdma) +{ + return fdma->db_index != fdma->n_dbs; +} + +/* Check if the FDMA has marked this DB as done. */ +static inline bool fdma_db_is_done(struct fdma_db *db) +{ + return db->status & FDMA_DCB_STATUS_DONE; +} + +/* Get the length of a DB. */ +static inline int fdma_db_len_get(struct fdma_db *db) +{ + return FDMA_DCB_STATUS_BLOCKL(db->status); +} + +/* Set the length of a DB. */ +static inline void fdma_dcb_len_set(struct fdma_dcb *dcb, u32 len) +{ + dcb->info = FDMA_DCB_INFO_DATAL(len); +} + +/* Get a DB by index. */ +static inline struct fdma_db *fdma_db_get(struct fdma *fdma, int dcb_idx, + int db_idx) +{ + return &fdma->dcbs[dcb_idx].db[db_idx]; +} + +/* Get the next DB. */ +static inline struct fdma_db *fdma_db_next_get(struct fdma *fdma) +{ + return fdma_db_get(fdma, fdma->dcb_index, fdma->db_index); +} + +/* Get a DCB by index. */ +static inline struct fdma_dcb *fdma_dcb_get(struct fdma *fdma, int dcb_idx) +{ + return &fdma->dcbs[dcb_idx]; +} + +/* Get the next DCB. */ +static inline struct fdma_dcb *fdma_dcb_next_get(struct fdma *fdma) +{ + return fdma_dcb_get(fdma, fdma->dcb_index); +} + +/* Check if the FDMA has frames ready for extraction. */ +static inline bool fdma_has_frames(struct fdma *fdma) +{ + return fdma_db_is_done(fdma_db_next_get(fdma)); +} + +/* Get a nextptr by index */ +static inline int fdma_nextptr_cb(struct fdma *fdma, int dcb_idx, u64 *nextptr) +{ + *nextptr = fdma->dma + (sizeof(struct fdma_dcb) * dcb_idx); + return 0; +} + +/* Get the DMA address of a dataptr, by index. This function is only applicable + * if the dataptr addresses and DCB's are in contiguous memory and the driver + * supports XDP. + */ +static inline u64 fdma_dataptr_get_contiguous(struct fdma *fdma, int dcb_idx, + int db_idx) +{ + return fdma->dma + (sizeof(struct fdma_dcb) * fdma->n_dcbs) + + (dcb_idx * fdma->n_dbs + db_idx) * fdma->db_size + + XDP_PACKET_HEADROOM; +} + +/* Get the virtual address of a dataptr, by index. This function is only + * applicable if the dataptr addresses and DCB's are in contiguous memory and + * the driver supports XDP. + */ +static inline void *fdma_dataptr_virt_get_contiguous(struct fdma *fdma, + int dcb_idx, int db_idx) +{ + return (u8 *)fdma->dcbs + (sizeof(struct fdma_dcb) * fdma->n_dcbs) + + (dcb_idx * fdma->n_dbs + db_idx) * fdma->db_size + + XDP_PACKET_HEADROOM; +} + +/* Check if this DCB is the last used DCB. */ +static inline bool fdma_is_last(struct fdma *fdma, struct fdma_dcb *dcb) +{ + return dcb == fdma->last_dcb; +} + +int fdma_dcbs_init(struct fdma *fdma, u64 info, u64 status); +int fdma_db_add(struct fdma *fdma, int dcb_idx, int db_idx, u64 status); +int fdma_dcb_add(struct fdma *fdma, int dcb_idx, u64 info, u64 status); +int __fdma_dcb_add(struct fdma *fdma, int dcb_idx, u64 info, u64 status, + int (*dcb_cb)(struct fdma *fdma, int dcb_idx, u64 *nextptr), + int (*db_cb)(struct fdma *fdma, int dcb_idx, int db_idx, + u64 *dataptr)); + +int fdma_alloc_coherent(struct device *dev, struct fdma *fdma); +int fdma_alloc_phys(struct fdma *fdma); + +void fdma_free_coherent(struct device *dev, struct fdma *fdma); +void fdma_free_phys(struct fdma *fdma); + +u32 fdma_get_size(struct fdma *fdma); +u32 fdma_get_size_contiguous(struct fdma *fdma); + +#endif |