Re: [PATCH 4/6] ethernet: stmmac: fix dma physical address of descriptor when display ring
From: Florian Fainelli <f.fainelli@gmail.com>
Date: 2021-01-11 17:31:26
On 1/11/21 3:35 AM, Joakim Zhang wrote:
quoted hunk ↗ jump to hunk
Driver uses dma_alloc_coherent to allocate dma memory for descriptors, dma_alloc_coherent will return both the virtual address and physical address. AFAIK, virt_to_phys could not convert virtual address to physical address, for which memory is allocated by dma_alloc_coherent. Signed-off-by: Joakim Zhang <redacted> --- .../ethernet/stmicro/stmmac/dwmac4_descs.c | 5 +- .../net/ethernet/stmicro/stmmac/enh_desc.c | 5 +- drivers/net/ethernet/stmicro/stmmac/hwif.h | 3 +- .../net/ethernet/stmicro/stmmac/norm_desc.c | 5 +- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 50 ++++++++++++------- 5 files changed, 44 insertions(+), 24 deletions(-)diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c index c6540b003b43..8e1ee33ba1e6 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c@@ -402,7 +402,8 @@ static void dwmac4_rd_set_tx_ic(struct dma_desc *p) p->des2 |= cpu_to_le32(TDES2_INTERRUPT_ON_COMPLETION); } -static void dwmac4_display_ring(void *head, unsigned int size, bool rx) +static void dwmac4_display_ring(void *head, unsigned int size, bool rx, + unsigned int dma_rx_phy, unsigned int desc_size) { struct dma_desc *p = (struct dma_desc *)head; int i;@@ -411,7 +412,7 @@ static void dwmac4_display_ring(void *head, unsigned int size, bool rx) for (i = 0; i < size; i++) { pr_info("%03d [0x%x]: 0x%x 0x%x 0x%x 0x%x\n", - i, (unsigned int)virt_to_phys(p), + i, (unsigned int)(dma_rx_phy + i * desc_size),
This code will probably not work correctly on a machine with physical addresses greater than 32-bit anyway and the address bits would be truncated then, cannot you use a phy_addr_t or dma_addr_t and use %pa as far as the printk format goes? -- Florian