From: Jamin Lin <jamin_...@aspeedtech.com> 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> Reviewed-by: Cédric Le Goater <c...@redhat.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 74aa5e0a160b..3ae22cb052d8 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", -- 2.46.0