Since the kernel does not check the interleave capability, a 3-way, 6-way, 12-way or 16-way region can be create normally.
Applications can access the memory of 16-way region normally because qemu can convert hpa to dpa correctly for the power of 2 interleave ways, after kernel implementing the check, this kind of region will not be created any more. For non power of 2 interleave ways, applications could not access the memory normally and may occur some unexpected behaviors, such as segmentation fault. So implements this feature is needed. Link: https://lore.kernel.org/linux-cxl/3e84b919-7631-d1db-3e1d-33000f3f3...@fujitsu.com/ Signed-off-by: Yao Xingtao <yaoxt.f...@fujitsu.com> --- hw/mem/cxl_type3.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c index b0a7e9f11b..d6ef784e96 100644 --- a/hw/mem/cxl_type3.c +++ b/hw/mem/cxl_type3.c @@ -805,10 +805,17 @@ static bool cxl_type3_dpa(CXLType3Dev *ct3d, hwaddr host_addr, uint64_t *dpa) continue; } - *dpa = dpa_base + - ((MAKE_64BIT_MASK(0, 8 + ig) & hpa_offset) | - ((MAKE_64BIT_MASK(8 + ig + iw, 64 - 8 - ig - iw) & hpa_offset) - >> iw)); + if (iw < 8) { + *dpa = dpa_base + + ((MAKE_64BIT_MASK(0, 8 + ig) & hpa_offset) | + ((MAKE_64BIT_MASK(8 + ig + iw, 64 - 8 - ig - iw) & hpa_offset) + >> iw)); + } else { + *dpa = dpa_base + + ((MAKE_64BIT_MASK(0, 8 + ig) & hpa_offset) | + ((((MAKE_64BIT_MASK(ig + iw, 64 - ig - iw) & hpa_offset) + >> (ig + iw)) / 3) << (ig + 8))); + } return true; } @@ -906,6 +913,9 @@ static void ct3d_reset(DeviceState *dev) uint32_t *write_msk = ct3d->cxl_cstate.crb.cache_mem_regs_write_mask; cxl_component_register_init_common(reg_state, write_msk, CXL2_TYPE3_DEVICE); + ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, 3_6_12_WAY, 1); + ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, 16_WAY, 1); + cxl_device_register_init_t3(ct3d); /* -- 2.37.3