Allow 64-bit DMA on AHCI. If not supported by the host controller, at least print a message and fail.

Signed-off-by: Roman Kapl rka@sysgo.com --- v1 -> v2: v1 was a mistake v2 -> v3: suppress warning on 32-bit phys addr platforms by using the upper/lower 32 bits macros

drivers/ata/ahci.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 21a89eba5a..d10f9f0bf8 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -50,6 +50,8 @@ struct ahci_uc_priv *probe_ent = NULL; #define WAIT_MS_FLUSH 5000 #define WAIT_MS_LINKUP 200

+#define AHCI_CAP_S64A BIT(31) + __weak void __iomem *ahci_port_base(void __iomem *base, u32 port) { return base + 0x100 + (port * 0x80); @@ -503,9 +505,15 @@ static int ahci_fill_sg(struct ahci_uc_priv *uc_priv, u8 port, }

for (i = 0; i < sg_count; i++) { - ahci_sg->addr = - cpu_to_le32((unsigned long) buf + i * MAX_DATA_BYTE_COUNT); - ahci_sg->addr_hi = 0; + /* We assume virt=phys */ + phys_addr_t pa = (unsigned long)buf + i * MAX_DATA_BYTE_COUNT; + + ahci_sg->addr = cpu_to_le32(lower_32_bits(pa)); + ahci_sg->addr_hi = cpu_to_le32(upper_32_bits(pa)); + if (ahci_sg->addr_hi && !(uc_priv->cap & AHCI_CAP_S64A)) { + printf("Error: DMA address too high\n"); + return -1; + } ahci_sg->flags_size = cpu_to_le32(0x3fffff & (buf_len < MAX_DATA_BYTE_COUNT ? (buf_len - 1)