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-rw-r--r--drivers/net/ethernet/sfc/io.h178
1 files changed, 60 insertions, 118 deletions
diff --git a/drivers/net/ethernet/sfc/io.h b/drivers/net/ethernet/sfc/io.h
index 96759aee1c6c..ef374a8e05c3 100644
--- a/drivers/net/ethernet/sfc/io.h
+++ b/drivers/net/ethernet/sfc/io.h
@@ -1,11 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
/****************************************************************************
- * Driver for Solarflare Solarstorm network controllers and boards
+ * Driver for Solarflare network controllers and boards
* Copyright 2005-2006 Fen Systems Ltd.
- * Copyright 2006-2010 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.
+ * Copyright 2006-2013 Solarflare Communications Inc.
*/
#ifndef EFX_IO_H
@@ -20,46 +17,45 @@
*
**************************************************************************
*
- * Notes on locking strategy:
- *
- * Many CSRs are very wide and cannot be read or written atomically.
- * Writes from the host are buffered by the Bus Interface Unit (BIU)
- * up to 128 bits. 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.
- *
- * Writes to different CSRs and 64-bit SRAM words must be serialised,
- * since interleaved access can result in lost writes. We use
- * efx_nic::biu_lock for this.
+ * The EF10 architecture exposes very few registers to the host and
+ * most of them are only 32 bits wide. The only exceptions are the MC
+ * doorbell register pair, which has its own latching, and
+ * TX_DESC_UPD.
*
- * We also serialise reads from 128-bit CSRs and SRAM with the same
- * spinlock. This may not be necessary, but it doesn't really matter
- * as there are no such reads on the fast path.
+ * The TX_DESC_UPD DMA descriptor pointer is 128-bits but is a special
+ * case in the BIU to avoid the need for locking in the host:
*
- * 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
+ * - It is write-only.
+ * - The semantics of writing to this register is 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
+ * - If the host writes to the last dword address of the register
* (i.e. the high 32 bits) the underlying register will always be
* written. If the collector and the current write together do not
* provide values for all 128 bits of the register, the low 96 bits
* will be written as zero.
- * - 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
+/* Hardware issue requires that only 64-bit naturally aligned writes
+ * are seen by hardware. Its not strictly necessary to restrict to
+ * x86_64 arch, but done for safety since unusual write combining behaviour
+ * can break PIO.
+ */
+#ifdef CONFIG_X86_64
+/* PIO is a win only if write-combining is possible */
+#ifdef ioremap_wc
+#define EFX_USE_PIO 1
+#endif
+#endif
+
+static inline u32 efx_reg(struct efx_nic *efx, unsigned int reg)
+{
+ return efx->reg_base + reg;
+}
+
#ifdef EFX_USE_QWORD_IO
static inline void _efx_writeq(struct efx_nic *efx, __le64 value,
unsigned int reg)
@@ -83,7 +79,7 @@ static inline __le32 _efx_readd(struct efx_nic *efx, unsigned int reg)
}
/* Write a normal 128-bit CSR, locking as appropriate. */
-static inline void efx_writeo(struct efx_nic *efx, efx_oword_t *value,
+static inline void efx_writeo(struct efx_nic *efx, const efx_oword_t *value,
unsigned int reg)
{
unsigned long flags __attribute__ ((unused));
@@ -102,34 +98,11 @@ static inline void efx_writeo(struct efx_nic *efx, efx_oword_t *value,
_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,
+static inline void efx_writed(struct efx_nic *efx, const efx_dword_t *value,
unsigned int reg)
{
netif_vdbg(efx, hw, efx->net_dev,
@@ -158,27 +131,6 @@ static inline void efx_reado(struct efx_nic *efx, efx_oword_t *value,
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)
@@ -190,8 +142,9 @@ static inline void efx_readd(struct efx_nic *efx, efx_dword_t *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)
+static inline void
+efx_writeo_table(struct efx_nic *efx, const efx_oword_t *value,
+ unsigned int reg, unsigned int index)
{
efx_writeo(efx, value, reg + index * sizeof(efx_oword_t));
}
@@ -203,18 +156,24 @@ static inline void efx_reado_table(struct efx_nic *efx, efx_oword_t *value,
efx_reado(efx, value, reg + index * sizeof(efx_oword_t));
}
-/* Page-mapped register block size */
-#define EFX_PAGE_BLOCK_SIZE 0x2000
+/* default VI stride (step between per-VI registers) is 8K on EF10 and
+ * 64K on EF100
+ */
+#define EFX_DEFAULT_VI_STRIDE 0x2000
+#define EF100_DEFAULT_VI_STRIDE 0x10000
-/* Calculate offset to page-mapped register block */
-#define EFX_PAGED_REG(page, reg) \
- ((page) * EFX_PAGE_BLOCK_SIZE + (reg))
+/* Calculate offset to page-mapped register */
+static inline unsigned int efx_paged_reg(struct efx_nic *efx, unsigned int page,
+ unsigned int reg)
+{
+ return page * efx->vi_stride + 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);
+ reg = efx_paged_reg(efx, page, reg);
netif_vdbg(efx, hw, efx->net_dev,
"writing register %x with " EFX_OWORD_FMT "\n", reg,
@@ -236,43 +195,26 @@ static inline void _efx_writeo_page(struct efx_nic *efx, efx_oword_t *value,
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)
+/* Write a page-mapped 32-bit CSR (EVQ_RPTR, EVQ_TMR (EF10), 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)
+static inline void
+_efx_writed_page(struct efx_nic *efx, const efx_dword_t *value,
+ unsigned int reg, unsigned int page)
{
- efx_writed(efx, value, EFX_PAGED_REG(page, reg));
+ efx_writed(efx, value, efx_paged_reg(efx, 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), \
+ BUILD_BUG_ON_ZERO((reg) != 0x180 && \
+ (reg) != 0x200 && \
+ (reg) != 0x400 && \
+ (reg) != 0x420 && \
+ (reg) != 0x830 && \
+ (reg) != 0x83c && \
+ (reg) != 0xa18 && \
+ (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 */