net: axienet: make the 64b addresable DMA depends on 64b archectures

Currently it is not safe to config the IP as 64-bit addressable on 32-bit
archectures, which cannot perform a double-word store on its descriptor
pointers. The pointer is 64-bit wide if the IP is configured as 64-bit,
and the device would process the partially updated pointer on some
states if the pointer was updated via two store-words. To prevent such
condition, we force a probe fail if we discover that the IP has 64-bit
capability but it is not running on a 64-Bit kernel.

This is a series of patch (1/2). The next patch must be applied in order
to make 64b DMA safe on 64b archectures.

Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reported-by: Max Hsu <max.hsu@sifive.com>
Reviewed-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Andy Chiu 2022-06-13 11:42:01 +08:00 committed by David S. Miller
parent a5b00f5b78
commit 00be43a74c
2 changed files with 40 additions and 24 deletions

View File

@ -547,6 +547,42 @@ static inline void axienet_iow(struct axienet_local *lp, off_t offset,
iowrite32(value, lp->regs + offset); iowrite32(value, lp->regs + offset);
} }
/**
* axienet_dma_out32 - Memory mapped Axi DMA register write.
* @lp: Pointer to axienet local structure
* @reg: Address offset from the base address of the Axi DMA core
* @value: Value to be written into the Axi DMA register
*
* This function writes the desired value into the corresponding Axi DMA
* register.
*/
static inline void axienet_dma_out32(struct axienet_local *lp,
off_t reg, u32 value)
{
iowrite32(value, lp->dma_regs + reg);
}
#ifdef CONFIG_64BIT
static void axienet_dma_out_addr(struct axienet_local *lp, off_t reg,
dma_addr_t addr)
{
axienet_dma_out32(lp, reg, lower_32_bits(addr));
if (lp->features & XAE_FEATURE_DMA_64BIT)
axienet_dma_out32(lp, reg + 4, upper_32_bits(addr));
}
#else /* CONFIG_64BIT */
static void axienet_dma_out_addr(struct axienet_local *lp, off_t reg,
dma_addr_t addr)
{
axienet_dma_out32(lp, reg, lower_32_bits(addr));
}
#endif /* CONFIG_64BIT */
/* Function prototypes visible in xilinx_axienet_mdio.c for other files */ /* Function prototypes visible in xilinx_axienet_mdio.c for other files */
int axienet_mdio_enable(struct axienet_local *lp); int axienet_mdio_enable(struct axienet_local *lp);
void axienet_mdio_disable(struct axienet_local *lp); void axienet_mdio_disable(struct axienet_local *lp);

View File

@ -133,30 +133,6 @@ static inline u32 axienet_dma_in32(struct axienet_local *lp, off_t reg)
return ioread32(lp->dma_regs + reg); return ioread32(lp->dma_regs + reg);
} }
/**
* axienet_dma_out32 - Memory mapped Axi DMA register write.
* @lp: Pointer to axienet local structure
* @reg: Address offset from the base address of the Axi DMA core
* @value: Value to be written into the Axi DMA register
*
* This function writes the desired value into the corresponding Axi DMA
* register.
*/
static inline void axienet_dma_out32(struct axienet_local *lp,
off_t reg, u32 value)
{
iowrite32(value, lp->dma_regs + reg);
}
static void axienet_dma_out_addr(struct axienet_local *lp, off_t reg,
dma_addr_t addr)
{
axienet_dma_out32(lp, reg, lower_32_bits(addr));
if (lp->features & XAE_FEATURE_DMA_64BIT)
axienet_dma_out32(lp, reg + 4, upper_32_bits(addr));
}
static void desc_set_phys_addr(struct axienet_local *lp, dma_addr_t addr, static void desc_set_phys_addr(struct axienet_local *lp, dma_addr_t addr,
struct axidma_bd *desc) struct axidma_bd *desc)
{ {
@ -2061,6 +2037,10 @@ static int axienet_probe(struct platform_device *pdev)
iowrite32(0x0, desc); iowrite32(0x0, desc);
} }
} }
if (!IS_ENABLED(CONFIG_64BIT) && lp->features & XAE_FEATURE_DMA_64BIT) {
dev_err(&pdev->dev, "64-bit addressable DMA is not compatible with 32-bit archecture\n");
goto cleanup_clk;
}
ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(addr_width)); ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(addr_width));
if (ret) { if (ret) {