[PATCH 2/3] staging: et131x: Use upper_32_bits() instead of '>> 32'

From: Mark Einon
Date: Fri Oct 19 2012 - 18:08:17 EST


>From a previous comment by Alan Cox:
'>> 32 of a 32bit value is undefined in C. The compiler is free
to do what it likes with this...'

Change all uses of '>> 32' to use upper_32_bits() and use
the corresponding lower_32_bits() to match.

Also remove an incorrect comment about dma alloc always returning 32bit
addresses.

Signed-off-by: Mark Einon <mark.einon@xxxxxxxxx>
---
drivers/staging/et131x/et131x.c | 55 ++++++++++++++++++---------------------
1 file changed, 25 insertions(+), 30 deletions(-)

diff --git a/drivers/staging/et131x/et131x.c b/drivers/staging/et131x/et131x.c
index 3fd8142..32f909a 100644
--- a/drivers/staging/et131x/et131x.c
+++ b/drivers/staging/et131x/et131x.c
@@ -1859,25 +1859,17 @@ static void et131x_config_rx_dma_regs(struct et131x_adapter *adapter)
/* Halt RXDMA to perform the reconfigure. */
et131x_rx_dma_disable(adapter);

- /* Load the completion writeback physical address
- *
- * NOTE : dma_alloc_coherent(), used above to alloc DMA regions,
- * ALWAYS returns SAC (32-bit) addresses. If DAC (64-bit) addresses
- * are ever returned, make sure the high part is retrieved here
- * before storing the adjusted address.
- */
- writel((u32) ((u64)rx_local->rx_status_bus >> 32),
- &rx_dma->dma_wb_base_hi);
- writel((u32) rx_local->rx_status_bus, &rx_dma->dma_wb_base_lo);
+ /* Load the completion writeback physical address */
+ writel(upper_32_bits(rx_local->rx_status_bus), &rx_dma->dma_wb_base_hi);
+ writel(lower_32_bits(rx_local->rx_status_bus), &rx_dma->dma_wb_base_lo);

memset(rx_local->rx_status_block, 0, sizeof(struct rx_status_block));

/* Set the address and parameters of the packet status ring into the
* 1310's registers
*/
- writel((u32) ((u64)rx_local->ps_ring_physaddr >> 32),
- &rx_dma->psr_base_hi);
- writel((u32) rx_local->ps_ring_physaddr, &rx_dma->psr_base_lo);
+ writel(upper_32_bits(rx_local->ps_ring_physaddr), &rx_dma->psr_base_hi);
+ writel(lower_32_bits(rx_local->ps_ring_physaddr), &rx_dma->psr_base_lo);
writel(rx_local->psr_num_entries - 1, &rx_dma->psr_num_des);
writel(0, &rx_dma->psr_full_offset);

@@ -1902,9 +1894,10 @@ static void et131x_config_rx_dma_regs(struct et131x_adapter *adapter)
/* Set the address and parameters of Free buffer ring 1 (and 0 if
* required) into the 1310's registers
*/
- writel((u32) (rx_local->fbr[0]->ring_physaddr >> 32),
+ writel(upper_32_bits(rx_local->fbr[0]->ring_physaddr),
&rx_dma->fbr1_base_hi);
- writel((u32) rx_local->fbr[0]->ring_physaddr, &rx_dma->fbr1_base_lo);
+ writel(lower_32_bits(rx_local->fbr[0]->ring_physaddr),
+ &rx_dma->fbr1_base_lo);
writel(rx_local->fbr[0]->num_entries - 1, &rx_dma->fbr1_num_des);
writel(ET_DMA10_WRAP, &rx_dma->fbr1_full_offset);

@@ -1926,9 +1919,10 @@ static void et131x_config_rx_dma_regs(struct et131x_adapter *adapter)
fbr_entry++;
}

- writel((u32) (rx_local->fbr[1]->ring_physaddr >> 32),
+ writel(upper_32_bits(rx_local->fbr[1]->ring_physaddr),
&rx_dma->fbr0_base_hi);
- writel((u32) rx_local->fbr[1]->ring_physaddr, &rx_dma->fbr0_base_lo);
+ writel(lower_32_bits(rx_local->fbr[1]->ring_physaddr),
+ &rx_dma->fbr0_base_lo);
writel(rx_local->fbr[1]->num_entries - 1, &rx_dma->fbr0_num_des);
writel(ET_DMA10_WRAP, &rx_dma->fbr0_full_offset);

@@ -1970,18 +1964,19 @@ static void et131x_config_tx_dma_regs(struct et131x_adapter *adapter)
struct txdma_regs __iomem *txdma = &adapter->regs->txdma;

/* Load the hardware with the start of the transmit descriptor ring. */
- writel((u32) ((u64)adapter->tx_ring.tx_desc_ring_pa >> 32),
+ writel(upper_32_bits(adapter->tx_ring.tx_desc_ring_pa),
&txdma->pr_base_hi);
- writel((u32) adapter->tx_ring.tx_desc_ring_pa,
+ writel(lower_32_bits(adapter->tx_ring.tx_desc_ring_pa),
&txdma->pr_base_lo);

/* Initialise the transmit DMA engine */
writel(NUM_DESC_PER_RING_TX - 1, &txdma->pr_num_des);

/* Load the completion writeback physical address */
- writel((u32)((u64)adapter->tx_ring.tx_status_pa >> 32),
- &txdma->dma_wb_base_hi);
- writel((u32)adapter->tx_ring.tx_status_pa, &txdma->dma_wb_base_lo);
+ writel(upper_32_bits(adapter->tx_ring.tx_status_pa),
+ &txdma->dma_wb_base_hi);
+ writel(lower_32_bits(adapter->tx_ring.tx_status_pa),
+ &txdma->dma_wb_base_lo);

*adapter->tx_ring.tx_status = 0;

@@ -2460,16 +2455,16 @@ static int et131x_rx_dma_memory_alloc(struct et131x_adapter *adapter)
* so the device can access it
*/
rx_ring->fbr[0]->bus_high[index] =
- (u32) (fbr1_tmp_physaddr >> 32);
+ upper_32_bits(fbr1_tmp_physaddr);
rx_ring->fbr[0]->bus_low[index] =
- (u32) fbr1_tmp_physaddr;
+ lower_32_bits(fbr1_tmp_physaddr);

fbr1_tmp_physaddr += rx_ring->fbr[0]->buffsize;

rx_ring->fbr[0]->buffer1[index] =
- rx_ring->fbr[0]->virt[index];
+ rx_ring->fbr[0]->virt[index];
rx_ring->fbr[0]->buffer2[index] =
- rx_ring->fbr[0]->virt[index] - 4;
+ rx_ring->fbr[0]->virt[index] - 4;
}
}

@@ -2508,16 +2503,16 @@ static int et131x_rx_dma_memory_alloc(struct et131x_adapter *adapter)
(j * rx_ring->fbr[1]->buffsize) + fbr0_offset;

rx_ring->fbr[1]->bus_high[index] =
- (u32) (fbr0_tmp_physaddr >> 32);
+ upper_32_bits(fbr0_tmp_physaddr);
rx_ring->fbr[1]->bus_low[index] =
- (u32) fbr0_tmp_physaddr;
+ lower_32_bits(fbr0_tmp_physaddr);

fbr0_tmp_physaddr += rx_ring->fbr[1]->buffsize;

rx_ring->fbr[1]->buffer1[index] =
- rx_ring->fbr[1]->virt[index];
+ rx_ring->fbr[1]->virt[index];
rx_ring->fbr[1]->buffer2[index] =
- rx_ring->fbr[1]->virt[index] - 4;
+ rx_ring->fbr[1]->virt[index] - 4;
}
}
#endif
--
1.7.9.5

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