ASPEED AST2700 SOC is a 64 bits quad core CPUs (Cortex-a35)
and the base address of dram is "0x4 00000000" which
is 64bits address.
The AST2700 support the maximum DRAM size is 8 GB.
The DRAM physical address range is from "0x4_0000_0000" to
"0x5_FFFF_FFFF".
The DRAM offset range is from "0x0_0000_0000" to
"0x1_FFFF_FFFF" and it is enough to use bits [33:0]
saving the dram offset.
Therefore, save the high part physical address bit[1:0]
of Tx/Rx buffer address as dma_dram_offset bit[33:32].
It does not need to decrease the dram physical
high part address for DMA operation.
(high part physical address bit[7:0] – 4)
Signed-off-by: Jamin Lin <jamin_...@aspeedtech.com>
---
hw/i2c/aspeed_i2c.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/hw/i2c/aspeed_i2c.c b/hw/i2c/aspeed_i2c.c
index c1ff80b1cf..44c3c39233 100644
--- a/hw/i2c/aspeed_i2c.c
+++ b/hw/i2c/aspeed_i2c.c
@@ -743,6 +743,14 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus,
hwaddr offset,
__func__);
break;
+ /*
+ * The AST2700 support the maximum DRAM size is 8 GB.
+ * The DRAM offset range is from 0x0_0000_0000 to
+ * 0x1_FFFF_FFFF and it is enough to use bits [33:0]
+ * saving the dram offset.
+ * Therefore, save the high part physical address bit[1:0]
+ * of Tx/Rx buffer address as dma_dram_offset bit[33:32].
+ */
case A_I2CM_DMA_TX_ADDR_HI:
if (!aic->has_dma64) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA 64 bits support\n",
@@ -752,6 +760,8 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus,
hwaddr offset,
bus->regs[R_I2CM_DMA_TX_ADDR_HI] = FIELD_EX32(value,
I2CM_DMA_TX_ADDR_HI,
ADDR_HI);
+ bus->dma_dram_offset = deposit64(bus->dma_dram_offset, 32, 32,
+ extract32(value, 0, 2));
break;
case A_I2CM_DMA_RX_ADDR_HI:
if (!aic->has_dma64) {
@@ -762,6 +772,8 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus,
hwaddr offset,
bus->regs[R_I2CM_DMA_RX_ADDR_HI] = FIELD_EX32(value,
I2CM_DMA_RX_ADDR_HI,
ADDR_HI);
+ bus->dma_dram_offset = deposit64(bus->dma_dram_offset, 32, 32,
+ extract32(value, 0, 2));
break;
case A_I2CS_DMA_TX_ADDR_HI:
qemu_log_mask(LOG_UNIMP,
@@ -777,6 +789,8 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus,
hwaddr offset,
bus->regs[R_I2CS_DMA_RX_ADDR_HI] = FIELD_EX32(value,
I2CS_DMA_RX_ADDR_HI,
ADDR_HI);
+ bus->dma_dram_offset = deposit64(bus->dma_dram_offset, 32, 32,
+ extract32(value, 0, 2));
break;
default:
qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n",
--
2.34.1
