1 files changed, 243 insertions, 0 deletions

diff --git a/drivers/net/sfc/falcon_io.h b/drivers/net/sfc/falcon_io.h
new file mode 100644
index 000000000000..ea08184ddfa9
--- /dev/null
+++ b/drivers/net/sfc/falcon_io.h
@@ -0,0 +1,243 @@
+/****************************************************************************
+ * 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>
+#include "net_driver.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
+
+#define _falcon_writeq(efx, value, reg) \
+        __raw_writeq((__force u64) (value), (efx)->membase + (reg))
+#define _falcon_writel(efx, value, reg) \
+        __raw_writel((__force u32) (value), (efx)->membase + (reg))
+#define _falcon_readq(efx, reg) \
+        ((__force __le64) __raw_readq((efx)->membase + (reg)))
+#define _falcon_readl(efx, reg) \
+        ((__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. 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;
+
+        spin_lock_irqsave(&efx->biu_lock, flags);
+        falcon_writel(efx, value, FALCON_PAGED_REG(page, reg));
+        spin_unlock_irqrestore(&efx->biu_lock, flags);
+}
+
+#endif /* EFX_FALCON_IO_H */