[PATCH 04/12] net: ll_temac: Add support for non-native register endianness
From: Esben Haabendal
Date: Mon Apr 29 2019 - 04:34:53 EST
Replace the powerpc specific MMIO register access functions with the
generic big-endian mmio access functions, and add support for
little-endian access depending on configuration.
Big-endian access is maintained as the default, but little-endian can
be configured in device-tree binding or in platform data.
The temac_ior()/temac_iow() functions are replaced with macro wrappers
to avoid modifying existing code more than necessary.
Signed-off-by: Esben Haabendal <esben@xxxxxxxxxx>
---
drivers/net/ethernet/xilinx/ll_temac.h | 12 ++--
drivers/net/ethernet/xilinx/ll_temac_main.c | 87 +++++++++++++++++++++------
include/linux/platform_data/xilinx-ll-temac.h | 2 +
3 files changed, 79 insertions(+), 22 deletions(-)
diff --git a/drivers/net/ethernet/xilinx/ll_temac.h b/drivers/net/ethernet/xilinx/ll_temac.h
index e338b4f..23d8dd5 100644
--- a/drivers/net/ethernet/xilinx/ll_temac.h
+++ b/drivers/net/ethernet/xilinx/ll_temac.h
@@ -347,8 +347,10 @@ struct temac_local {
#ifdef CONFIG_PPC_DCR
dcr_host_t sdma_dcrs;
#endif
- u32 (*dma_in)(struct temac_local *, int);
- void (*dma_out)(struct temac_local *, int, u32);
+ u32 (*temac_ior)(struct temac_local *lp, int offset);
+ void (*temac_iow)(struct temac_local *lp, int offset, u32 value);
+ u32 (*dma_in)(struct temac_local *lp, int reg);
+ void (*dma_out)(struct temac_local *lp, int reg, u32 value);
int tx_irq;
int rx_irq;
@@ -372,9 +374,11 @@ struct temac_local {
int rx_bd_ci;
};
+/* Wrappers for temac_ior()/temac_iow() function pointers above */
+#define temac_ior(lp, o) ((lp)->temac_ior(lp, o))
+#define temac_iow(lp, o, v) ((lp)->temac_iow(lp, o, v))
+
/* xilinx_temac.c */
-u32 temac_ior(struct temac_local *lp, int offset);
-void temac_iow(struct temac_local *lp, int offset, u32 value);
int temac_indirect_busywait(struct temac_local *lp);
u32 temac_indirect_in32(struct temac_local *lp, int reg);
void temac_indirect_out32(struct temac_local *lp, int reg, u32 value);
diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index bcafb89..58c6713 100644
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c
@@ -63,14 +63,24 @@
* Low level register access functions
*/
-u32 temac_ior(struct temac_local *lp, int offset)
+u32 _temac_ior_be(struct temac_local *lp, int offset)
{
- return in_be32(lp->regs + offset);
+ return ioread32be(lp->regs + offset);
}
-void temac_iow(struct temac_local *lp, int offset, u32 value)
+void _temac_iow_be(struct temac_local *lp, int offset, u32 value)
{
- out_be32(lp->regs + offset, value);
+ return iowrite32be(value, lp->regs + offset);
+}
+
+u32 _temac_ior_le(struct temac_local *lp, int offset)
+{
+ return ioread32(lp->regs + offset);
+}
+
+void _temac_iow_le(struct temac_local *lp, int offset, u32 value)
+{
+ return iowrite32(value, lp->regs + offset);
}
int temac_indirect_busywait(struct temac_local *lp)
@@ -121,23 +131,35 @@ void temac_indirect_out32(struct temac_local *lp, int reg, u32 value)
}
/**
- * temac_dma_in32 - Memory mapped DMA read, this function expects a
- * register input that is based on DCR word addresses which
- * are then converted to memory mapped byte addresses
+ * temac_dma_in32_* - Memory mapped DMA read, these function expects a
+ * register input that is based on DCR word addresses which are then
+ * converted to memory mapped byte addresses. To be assigned to
+ * lp->dma_in32.
*/
-static u32 temac_dma_in32(struct temac_local *lp, int reg)
+static u32 temac_dma_in32_be(struct temac_local *lp, int reg)
{
- return in_be32(lp->sdma_regs + (reg << 2));
+ return ioread32be(lp->sdma_regs + (reg << 2));
+}
+
+static u32 temac_dma_in32_le(struct temac_local *lp, int reg)
+{
+ return ioread32(lp->sdma_regs + (reg << 2));
}
/**
- * temac_dma_out32 - Memory mapped DMA read, this function expects a
- * register input that is based on DCR word addresses which
- * are then converted to memory mapped byte addresses
+ * temac_dma_out32_* - Memory mapped DMA read, these function expects
+ * a register input that is based on DCR word addresses which are then
+ * converted to memory mapped byte addresses. To be assigned to
+ * lp->dma_out32.
*/
-static void temac_dma_out32(struct temac_local *lp, int reg, u32 value)
+static void temac_dma_out32_be(struct temac_local *lp, int reg, u32 value)
+{
+ iowrite32be(value, lp->sdma_regs + (reg << 2));
+}
+
+static void temac_dma_out32_le(struct temac_local *lp, int reg, u32 value)
{
- out_be32(lp->sdma_regs + (reg << 2), value);
+ iowrite32(value, lp->sdma_regs + (reg << 2));
}
/* DMA register access functions can be DCR based or memory mapped.
@@ -1024,6 +1046,7 @@ static int temac_probe(struct platform_device *pdev)
struct resource *res;
const void *addr;
__be32 *p;
+ bool little_endian;
int rc = 0;
/* Init network device structure */
@@ -1068,6 +1091,24 @@ static int temac_probe(struct platform_device *pdev)
return PTR_ERR(lp->regs);
}
+ /* Select register access functions with the specified
+ * endianness mode. Default for OF devices is big-endian.
+ */
+ little_endian = false;
+ if (temac_np) {
+ if (of_get_property(temac_np, "little-endian", NULL))
+ little_endian = true;
+ } else if (pdata) {
+ little_endian = pdata->reg_little_endian;
+ }
+ if (little_endian) {
+ lp->temac_ior = _temac_ior_le;
+ lp->temac_iow = _temac_iow_le;
+ } else {
+ lp->temac_ior = _temac_ior_be;
+ lp->temac_iow = _temac_iow_be;
+ }
+
/* Setup checksum offload, but default to off if not specified */
lp->temac_features = 0;
if (temac_np) {
@@ -1111,8 +1152,13 @@ static int temac_probe(struct platform_device *pdev)
of_node_put(dma_np);
return PTR_ERR(lp->sdma_regs);
}
- lp->dma_in = temac_dma_in32;
- lp->dma_out = temac_dma_out32;
+ if (of_get_property(dma_np, "little-endian", NULL)) {
+ lp->dma_in = temac_dma_in32_le;
+ lp->dma_out = temac_dma_out32_le;
+ } else {
+ lp->dma_in = temac_dma_in32_be;
+ lp->dma_out = temac_dma_out32_be;
+ }
dev_dbg(&pdev->dev, "MEM base: %p\n", lp->sdma_regs);
}
@@ -1132,8 +1178,13 @@ static int temac_probe(struct platform_device *pdev)
"could not map DMA registers\n");
return PTR_ERR(lp->sdma_regs);
}
- lp->dma_in = temac_dma_in32;
- lp->dma_out = temac_dma_out32;
+ if (pdata->dma_little_endian) {
+ lp->dma_in = temac_dma_in32_le;
+ lp->dma_out = temac_dma_out32_le;
+ } else {
+ lp->dma_in = temac_dma_in32_be;
+ lp->dma_out = temac_dma_out32_be;
+ }
/* Get DMA RX and TX interrupts */
lp->rx_irq = platform_get_irq(pdev, 0);
diff --git a/include/linux/platform_data/xilinx-ll-temac.h b/include/linux/platform_data/xilinx-ll-temac.h
index 82e2f80..af87927 100644
--- a/include/linux/platform_data/xilinx-ll-temac.h
+++ b/include/linux/platform_data/xilinx-ll-temac.h
@@ -14,6 +14,8 @@ struct ll_temac_platform_data {
unsigned long long mdio_bus_id; /* Unique id for MDIO bus */
int phy_addr; /* Address of the PHY to connect to */
phy_interface_t phy_interface; /* PHY interface mode */
+ bool reg_little_endian; /* Little endian TEMAC register access */
+ bool dma_little_endian; /* Little endian DMA register access */
};
#endif /* __LINUX_XILINX_LL_TEMAC_H */
--
2.4.11