| /**************************************************************************** |
| * Driver for Solarflare Solarstorm network controllers and boards |
| * Copyright 2005-2006 Fen Systems Ltd. |
| * Copyright 2006-2008 Solarflare Communications Inc. |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 as published |
| * by the Free Software Foundation, incorporated herein by reference. |
| */ |
| |
| #ifndef EFX_FALCON_IO_H |
| #define EFX_FALCON_IO_H |
| |
| #include <linux/io.h> |
| #include <linux/spinlock.h> |
| |
| /************************************************************************** |
| * |
| * Falcon hardware access |
| * |
| ************************************************************************** |
| * |
| * Notes on locking strategy: |
| * |
| * Most Falcon registers require 16-byte (or 8-byte, for SRAM |
| * registers) atomic writes which necessitates locking. |
| * Under normal operation few writes to the Falcon BAR are made and these |
| * registers (EVQ_RPTR_REG, RX_DESC_UPD_REG and TX_DESC_UPD_REG) are special |
| * cased to allow 4-byte (hence lockless) accesses. |
| * |
| * It *is* safe to write to these 4-byte registers in the middle of an |
| * access to an 8-byte or 16-byte register. We therefore use a |
| * spinlock to protect accesses to the larger registers, but no locks |
| * for the 4-byte registers. |
| * |
| * A write barrier is needed to ensure that DW3 is written after DW0/1/2 |
| * due to the way the 16byte registers are "collected" in the Falcon BIU |
| * |
| * We also lock when carrying out reads, to ensure consistency of the |
| * data (made possible since the BIU reads all 128 bits into a cache). |
| * Reads are very rare, so this isn't a significant performance |
| * impact. (Most data transferred from NIC to host is DMAed directly |
| * into host memory). |
| * |
| * I/O BAR access uses locks for both reads and writes (but is only provided |
| * for testing purposes). |
| */ |
| |
| /* Special buffer descriptors (Falcon SRAM) */ |
| #define BUF_TBL_KER_A1 0x18000 |
| #define BUF_TBL_KER_B0 0x800000 |
| |
| |
| #if BITS_PER_LONG == 64 |
| #define FALCON_USE_QWORD_IO 1 |
| #endif |
| |
| #ifdef FALCON_USE_QWORD_IO |
| static inline void _falcon_writeq(struct efx_nic *efx, __le64 value, |
| unsigned int reg) |
| { |
| __raw_writeq((__force u64)value, efx->membase + reg); |
| } |
| static inline __le64 _falcon_readq(struct efx_nic *efx, unsigned int reg) |
| { |
| return (__force __le64)__raw_readq(efx->membase + reg); |
| } |
| #endif |
| |
| static inline void _falcon_writel(struct efx_nic *efx, __le32 value, |
| unsigned int reg) |
| { |
| __raw_writel((__force u32)value, efx->membase + reg); |
| } |
| static inline __le32 _falcon_readl(struct efx_nic *efx, unsigned int reg) |
| { |
| return (__force __le32)__raw_readl(efx->membase + reg); |
| } |
| |
| /* Writes to a normal 16-byte Falcon register, locking as appropriate. */ |
| static inline void falcon_write(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg) |
| { |
| unsigned long flags; |
| |
| EFX_REGDUMP(efx, "writing register %x with " EFX_OWORD_FMT "\n", reg, |
| EFX_OWORD_VAL(*value)); |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| #ifdef FALCON_USE_QWORD_IO |
| _falcon_writeq(efx, value->u64[0], reg + 0); |
| wmb(); |
| _falcon_writeq(efx, value->u64[1], reg + 8); |
| #else |
| _falcon_writel(efx, value->u32[0], reg + 0); |
| _falcon_writel(efx, value->u32[1], reg + 4); |
| _falcon_writel(efx, value->u32[2], reg + 8); |
| wmb(); |
| _falcon_writel(efx, value->u32[3], reg + 12); |
| #endif |
| mmiowb(); |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| } |
| |
| /* Writes to an 8-byte Falcon SRAM register, locking as appropriate. */ |
| static inline void falcon_write_sram(struct efx_nic *efx, efx_qword_t *value, |
| unsigned int index) |
| { |
| unsigned int reg = efx->type->buf_tbl_base + (index * sizeof(*value)); |
| unsigned long flags; |
| |
| EFX_REGDUMP(efx, "writing SRAM register %x with " EFX_QWORD_FMT "\n", |
| reg, EFX_QWORD_VAL(*value)); |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| #ifdef FALCON_USE_QWORD_IO |
| _falcon_writeq(efx, value->u64[0], reg + 0); |
| #else |
| _falcon_writel(efx, value->u32[0], reg + 0); |
| wmb(); |
| _falcon_writel(efx, value->u32[1], reg + 4); |
| #endif |
| mmiowb(); |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| } |
| |
| /* Write dword to Falcon register that allows partial writes |
| * |
| * Some Falcon registers (EVQ_RPTR_REG, RX_DESC_UPD_REG and |
| * TX_DESC_UPD_REG) can be written to as a single dword. This allows |
| * for lockless writes. |
| */ |
| static inline void falcon_writel(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg) |
| { |
| EFX_REGDUMP(efx, "writing partial register %x with "EFX_DWORD_FMT"\n", |
| reg, EFX_DWORD_VAL(*value)); |
| |
| /* No lock required */ |
| _falcon_writel(efx, value->u32[0], reg); |
| } |
| |
| /* Read from a Falcon register |
| * |
| * This reads an entire 16-byte Falcon register in one go, locking as |
| * appropriate. It is essential to read the first dword first, as this |
| * prompts Falcon to load the current value into the shadow register. |
| */ |
| static inline void falcon_read(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| value->u32[0] = _falcon_readl(efx, reg + 0); |
| rmb(); |
| value->u32[1] = _falcon_readl(efx, reg + 4); |
| value->u32[2] = _falcon_readl(efx, reg + 8); |
| value->u32[3] = _falcon_readl(efx, reg + 12); |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| |
| EFX_REGDUMP(efx, "read from register %x, got " EFX_OWORD_FMT "\n", reg, |
| EFX_OWORD_VAL(*value)); |
| } |
| |
| /* This reads an 8-byte Falcon SRAM entry in one go. */ |
| static inline void falcon_read_sram(struct efx_nic *efx, efx_qword_t *value, |
| unsigned int index) |
| { |
| unsigned int reg = efx->type->buf_tbl_base + (index * sizeof(*value)); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| #ifdef FALCON_USE_QWORD_IO |
| value->u64[0] = _falcon_readq(efx, reg + 0); |
| #else |
| value->u32[0] = _falcon_readl(efx, reg + 0); |
| rmb(); |
| value->u32[1] = _falcon_readl(efx, reg + 4); |
| #endif |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| |
| EFX_REGDUMP(efx, "read from SRAM register %x, got "EFX_QWORD_FMT"\n", |
| reg, EFX_QWORD_VAL(*value)); |
| } |
| |
| /* Read dword from Falcon register that allows partial writes (sic) */ |
| static inline void falcon_readl(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg) |
| { |
| value->u32[0] = _falcon_readl(efx, reg); |
| EFX_REGDUMP(efx, "read from register %x, got "EFX_DWORD_FMT"\n", |
| reg, EFX_DWORD_VAL(*value)); |
| } |
| |
| /* Write to a register forming part of a table */ |
| static inline void falcon_write_table(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg, unsigned int index) |
| { |
| falcon_write(efx, value, reg + index * sizeof(efx_oword_t)); |
| } |
| |
| /* Read to a register forming part of a table */ |
| static inline void falcon_read_table(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg, unsigned int index) |
| { |
| falcon_read(efx, value, reg + index * sizeof(efx_oword_t)); |
| } |
| |
| /* Write to a dword register forming part of a table */ |
| static inline void falcon_writel_table(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg, unsigned int index) |
| { |
| falcon_writel(efx, value, reg + index * sizeof(efx_oword_t)); |
| } |
| |
| /* Page-mapped register block size */ |
| #define FALCON_PAGE_BLOCK_SIZE 0x2000 |
| |
| /* Calculate offset to page-mapped register block */ |
| #define FALCON_PAGED_REG(page, reg) \ |
| ((page) * FALCON_PAGE_BLOCK_SIZE + (reg)) |
| |
| /* As for falcon_write(), but for a page-mapped register. */ |
| static inline void falcon_write_page(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg, unsigned int page) |
| { |
| falcon_write(efx, value, FALCON_PAGED_REG(page, reg)); |
| } |
| |
| /* As for falcon_writel(), but for a page-mapped register. */ |
| static inline void falcon_writel_page(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg, unsigned int page) |
| { |
| falcon_writel(efx, value, FALCON_PAGED_REG(page, reg)); |
| } |
| |
| /* Write dword to Falcon page-mapped register with an extra lock. |
| * |
| * As for falcon_writel_page(), but for a register that suffers from |
| * SFC bug 3181. If writing to page 0, take out a lock so the BIU |
| * collector cannot be confused. |
| */ |
| static inline void falcon_writel_page_locked(struct efx_nic *efx, |
| efx_dword_t *value, |
| unsigned int reg, |
| unsigned int page) |
| { |
| unsigned long flags = 0; |
| |
| if (page == 0) |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| falcon_writel(efx, value, FALCON_PAGED_REG(page, reg)); |
| if (page == 0) |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| } |
| |
| #endif /* EFX_FALCON_IO_H */ |