| /**************************************************************************** |
| * Driver for Solarflare Solarstorm network controllers and boards |
| * Copyright 2005-2006 Fen Systems Ltd. |
| * Copyright 2006-2009 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_IO_H |
| #define EFX_IO_H |
| |
| #include <linux/io.h> |
| #include <linux/spinlock.h> |
| |
| /************************************************************************** |
| * |
| * NIC register I/O |
| * |
| ************************************************************************** |
| * |
| * Notes on locking strategy: |
| * |
| * Most CSRs are 128-bit (oword) and therefore cannot be read or |
| * written atomically. Access from the host is buffered by the Bus |
| * Interface Unit (BIU). Whenever the host reads from the lowest |
| * address of such a register, or from the address of a different such |
| * register, the BIU latches the register's value. Subsequent reads |
| * from higher addresses of the same register will read the latched |
| * value. Whenever the host writes part of such a register, the BIU |
| * collects the written value and does not write to the underlying |
| * register until all 4 dwords have been written. A similar buffering |
| * scheme applies to host access to the NIC's 64-bit SRAM. |
| * |
| * Access to different CSRs and 64-bit SRAM words must be serialised, |
| * since interleaved access can result in lost writes or lost |
| * information from read-to-clear fields. We use efx_nic::biu_lock |
| * for this. (We could use separate locks for read and write, but |
| * this is not normally a performance bottleneck.) |
| * |
| * The DMA descriptor pointers (RX_DESC_UPD and TX_DESC_UPD) are |
| * 128-bit but are special-cased in the BIU to avoid the need for |
| * locking in the host: |
| * |
| * - They are write-only. |
| * - The semantics of writing to these registers are such that |
| * replacing the low 96 bits with zero does not affect functionality. |
| * - If the host writes to the last dword address of such a register |
| * (i.e. the high 32 bits) the underlying register will always be |
| * written. If the collector does not hold values for the low 96 |
| * bits of the register, they will be written as zero. Writing to |
| * the last qword does not have this effect and must not be done. |
| * - If the host writes to the address of any other part of such a |
| * register while the collector already holds values for some other |
| * register, the write is discarded and the collector maintains its |
| * current state. |
| */ |
| |
| #if BITS_PER_LONG == 64 |
| #define EFX_USE_QWORD_IO 1 |
| #endif |
| |
| #ifdef EFX_USE_QWORD_IO |
| static inline void _efx_writeq(struct efx_nic *efx, __le64 value, |
| unsigned int reg) |
| { |
| __raw_writeq((__force u64)value, efx->membase + reg); |
| } |
| static inline __le64 _efx_readq(struct efx_nic *efx, unsigned int reg) |
| { |
| return (__force __le64)__raw_readq(efx->membase + reg); |
| } |
| #endif |
| |
| static inline void _efx_writed(struct efx_nic *efx, __le32 value, |
| unsigned int reg) |
| { |
| __raw_writel((__force u32)value, efx->membase + reg); |
| } |
| static inline __le32 _efx_readd(struct efx_nic *efx, unsigned int reg) |
| { |
| return (__force __le32)__raw_readl(efx->membase + reg); |
| } |
| |
| /* Write a normal 128-bit CSR, locking as appropriate. */ |
| static inline void efx_writeo(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg) |
| { |
| unsigned long flags __attribute__ ((unused)); |
| |
| netif_vdbg(efx, hw, efx->net_dev, |
| "writing register %x with " EFX_OWORD_FMT "\n", reg, |
| EFX_OWORD_VAL(*value)); |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| #ifdef EFX_USE_QWORD_IO |
| _efx_writeq(efx, value->u64[0], reg + 0); |
| _efx_writeq(efx, value->u64[1], reg + 8); |
| #else |
| _efx_writed(efx, value->u32[0], reg + 0); |
| _efx_writed(efx, value->u32[1], reg + 4); |
| _efx_writed(efx, value->u32[2], reg + 8); |
| _efx_writed(efx, value->u32[3], reg + 12); |
| #endif |
| mmiowb(); |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| } |
| |
| /* Write 64-bit SRAM through the supplied mapping, locking as appropriate. */ |
| static inline void efx_sram_writeq(struct efx_nic *efx, void __iomem *membase, |
| efx_qword_t *value, unsigned int index) |
| { |
| unsigned int addr = index * sizeof(*value); |
| unsigned long flags __attribute__ ((unused)); |
| |
| netif_vdbg(efx, hw, efx->net_dev, |
| "writing SRAM address %x with " EFX_QWORD_FMT "\n", |
| addr, EFX_QWORD_VAL(*value)); |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| #ifdef EFX_USE_QWORD_IO |
| __raw_writeq((__force u64)value->u64[0], membase + addr); |
| #else |
| __raw_writel((__force u32)value->u32[0], membase + addr); |
| __raw_writel((__force u32)value->u32[1], membase + addr + 4); |
| #endif |
| mmiowb(); |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| } |
| |
| /* Write a 32-bit CSR or the last dword of a special 128-bit CSR */ |
| static inline void efx_writed(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg) |
| { |
| netif_vdbg(efx, hw, efx->net_dev, |
| "writing register %x with "EFX_DWORD_FMT"\n", |
| reg, EFX_DWORD_VAL(*value)); |
| |
| /* No lock required */ |
| _efx_writed(efx, value->u32[0], reg); |
| } |
| |
| /* Read a 128-bit CSR, locking as appropriate. */ |
| static inline void efx_reado(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg) |
| { |
| unsigned long flags __attribute__ ((unused)); |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| value->u32[0] = _efx_readd(efx, reg + 0); |
| value->u32[1] = _efx_readd(efx, reg + 4); |
| value->u32[2] = _efx_readd(efx, reg + 8); |
| value->u32[3] = _efx_readd(efx, reg + 12); |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| |
| netif_vdbg(efx, hw, efx->net_dev, |
| "read from register %x, got " EFX_OWORD_FMT "\n", reg, |
| EFX_OWORD_VAL(*value)); |
| } |
| |
| /* Read 64-bit SRAM through the supplied mapping, locking as appropriate. */ |
| static inline void efx_sram_readq(struct efx_nic *efx, void __iomem *membase, |
| efx_qword_t *value, unsigned int index) |
| { |
| unsigned int addr = index * sizeof(*value); |
| unsigned long flags __attribute__ ((unused)); |
| |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| #ifdef EFX_USE_QWORD_IO |
| value->u64[0] = (__force __le64)__raw_readq(membase + addr); |
| #else |
| value->u32[0] = (__force __le32)__raw_readl(membase + addr); |
| value->u32[1] = (__force __le32)__raw_readl(membase + addr + 4); |
| #endif |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| |
| netif_vdbg(efx, hw, efx->net_dev, |
| "read from SRAM address %x, got "EFX_QWORD_FMT"\n", |
| addr, EFX_QWORD_VAL(*value)); |
| } |
| |
| /* Read a 32-bit CSR or SRAM */ |
| static inline void efx_readd(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg) |
| { |
| value->u32[0] = _efx_readd(efx, reg); |
| netif_vdbg(efx, hw, efx->net_dev, |
| "read from register %x, got "EFX_DWORD_FMT"\n", |
| reg, EFX_DWORD_VAL(*value)); |
| } |
| |
| /* Write a 128-bit CSR forming part of a table */ |
| static inline void efx_writeo_table(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg, unsigned int index) |
| { |
| efx_writeo(efx, value, reg + index * sizeof(efx_oword_t)); |
| } |
| |
| /* Read a 128-bit CSR forming part of a table */ |
| static inline void efx_reado_table(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg, unsigned int index) |
| { |
| efx_reado(efx, value, reg + index * sizeof(efx_oword_t)); |
| } |
| |
| /* Write a 32-bit CSR forming part of a table, or 32-bit SRAM */ |
| static inline void efx_writed_table(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg, unsigned int index) |
| { |
| efx_writed(efx, value, reg + index * sizeof(efx_oword_t)); |
| } |
| |
| /* Read a 32-bit CSR forming part of a table, or 32-bit SRAM */ |
| static inline void efx_readd_table(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg, unsigned int index) |
| { |
| efx_readd(efx, value, reg + index * sizeof(efx_dword_t)); |
| } |
| |
| /* Page-mapped register block size */ |
| #define EFX_PAGE_BLOCK_SIZE 0x2000 |
| |
| /* Calculate offset to page-mapped register block */ |
| #define EFX_PAGED_REG(page, reg) \ |
| ((page) * EFX_PAGE_BLOCK_SIZE + (reg)) |
| |
| /* Write the whole of RX_DESC_UPD or TX_DESC_UPD */ |
| static inline void _efx_writeo_page(struct efx_nic *efx, efx_oword_t *value, |
| unsigned int reg, unsigned int page) |
| { |
| reg = EFX_PAGED_REG(page, reg); |
| |
| netif_vdbg(efx, hw, efx->net_dev, |
| "writing register %x with " EFX_OWORD_FMT "\n", reg, |
| EFX_OWORD_VAL(*value)); |
| |
| #ifdef EFX_USE_QWORD_IO |
| _efx_writeq(efx, value->u64[0], reg + 0); |
| #else |
| _efx_writed(efx, value->u32[0], reg + 0); |
| _efx_writed(efx, value->u32[1], reg + 4); |
| #endif |
| _efx_writed(efx, value->u32[2], reg + 8); |
| _efx_writed(efx, value->u32[3], reg + 12); |
| } |
| #define efx_writeo_page(efx, value, reg, page) \ |
| _efx_writeo_page(efx, value, \ |
| reg + \ |
| BUILD_BUG_ON_ZERO((reg) != 0x830 && (reg) != 0xa10), \ |
| page) |
| |
| /* Write a page-mapped 32-bit CSR (EVQ_RPTR or the high bits of |
| * RX_DESC_UPD or TX_DESC_UPD) |
| */ |
| static inline void _efx_writed_page(struct efx_nic *efx, efx_dword_t *value, |
| unsigned int reg, unsigned int page) |
| { |
| efx_writed(efx, value, EFX_PAGED_REG(page, reg)); |
| } |
| #define efx_writed_page(efx, value, reg, page) \ |
| _efx_writed_page(efx, value, \ |
| reg + \ |
| BUILD_BUG_ON_ZERO((reg) != 0x400 && (reg) != 0x83c \ |
| && (reg) != 0xa1c), \ |
| page) |
| |
| /* Write TIMER_COMMAND. This is a page-mapped 32-bit CSR, but a bug |
| * in the BIU means that writes to TIMER_COMMAND[0] invalidate the |
| * collector register. |
| */ |
| static inline void _efx_writed_page_locked(struct efx_nic *efx, |
| efx_dword_t *value, |
| unsigned int reg, |
| unsigned int page) |
| { |
| unsigned long flags __attribute__ ((unused)); |
| |
| if (page == 0) { |
| spin_lock_irqsave(&efx->biu_lock, flags); |
| efx_writed(efx, value, EFX_PAGED_REG(page, reg)); |
| spin_unlock_irqrestore(&efx->biu_lock, flags); |
| } else { |
| efx_writed(efx, value, EFX_PAGED_REG(page, reg)); |
| } |
| } |
| #define efx_writed_page_locked(efx, value, reg, page) \ |
| _efx_writed_page_locked(efx, value, \ |
| reg + BUILD_BUG_ON_ZERO((reg) != 0x420), \ |
| page) |
| |
| #endif /* EFX_IO_H */ |