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[80.230.34.155]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-43618057f9esm6429989f8f.28.2026.02.04.08.48.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Feb 2026 08:48:16 -0800 (PST) Date: Wed, 4 Feb 2026 11:48:13 -0500 From: "Michael S. Tsirkin" To: Jonathan Cameron Cc: qemu-devel@nongnu.org, Davidlohr Bueso , linuxarm@huawei.com, linux-cxl@vger.kernel.org, Ravi Shankar , Marcel Apfelbaum , Markus Armbruster , Michael Roth Subject: Re: [PATCH qemu v6 6/7] hw/cxl: Support type3 HDM-DB Message-ID: <20260204114736-mutt-send-email-mst@kernel.org> References: <20260204121215.68897-1-Jonathan.Cameron@huawei.com> <20260204121215.68897-7-Jonathan.Cameron@huawei.com> <20260204082422-mutt-send-email-mst@kernel.org> <20260204084432-mutt-send-email-mst@kernel.org> <20260204152102.0000771f@huawei.com> Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20260204152102.0000771f@huawei.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: dwSCCz-xPwEds7mkSRPg-JFQ6WX2tE5pCncmPIawjWw_1770223698 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Feb 04, 2026 at 03:21:02PM +0000, Jonathan Cameron wrote: > On Wed, 4 Feb 2026 08:44:42 -0500 > "Michael S. Tsirkin" wrote: > > > On Wed, Feb 04, 2026 at 08:24:55AM -0500, Michael S. Tsirkin wrote: > > > On Wed, Feb 04, 2026 at 12:12:14PM +0000, Jonathan Cameron wrote: > > > > From: Davidlohr Bueso > > > > > > > > Add basic plumbing for memory expander devices that support Back > > > > Invalidation. This introduces a 'hdm-db=on|off' parameter and > > > > exposes the relevant BI RT/Decoder component cachemem registers. > > > > > > > > Some noteworthy properties: > > > > - Devices require enabling Flit mode across the CXL topology. > > > > - Explicit BI-ID commit is required. > > > > - HDM decoder support both host and dev coherency models. > > > > > > > > Tested-by: Dongjoo Seo > > > > Signed-off-by: Davidlohr Bueso > > > > Signed-off-by: Jonathan Cameron > > > > > > more troubles: > > > https://gitlab.com/mstredhat/qemu/-/jobs/12984846000 > > > > > > clang just as unhappy: > > > > https://gitlab.com/mstredhat/qemu/-/jobs/12984846060 > They both seem to be clang. > > Replicated. > > Ah. This old gotcha - at one point I got one of my compiler colleagues to report > it as a clang bug but he lost the argument vs the spec. Though I believe > it is being fixed in the C spec longer term. Yes the compiler actually says it's been fixed in C23. > I can't find the thread > now but we did discuss adding local scope in the macro a while back. > > Anyhow work around is to add scope to avoid label for the case statement > being followed by _Static_assert() > Despite smelling like a function, it's not and has special rules... > > Would you like a v7 or squash the following in? > Thanks > > Jonathan v7 pls. > > diff --git a/hw/cxl/cxl-component-utils.c b/hw/cxl/cxl-component-utils.c > index a3077184e230..07aabe331c44 100644 > --- a/hw/cxl/cxl-component-utils.c > +++ b/hw/cxl/cxl-component-utils.c > @@ -68,7 +68,7 @@ static uint64_t cxl_cache_mem_read_reg(void *opaque, hwaddr offset, > ComponentRegisters *cregs = &cxl_cstate->crb; > > switch (size) { > - case 4: > + case 4: { > QEMU_BUILD_BUG_ON(sizeof(*cregs->cache_mem_registers) != 4); > > if (offset == A_CXL_BI_RT_STATUS || > @@ -101,6 +101,7 @@ static uint64_t cxl_cache_mem_read_reg(void *opaque, hwaddr offset, > } > > return cregs->cache_mem_registers[offset / 4]; > + } > case 8: > qemu_log_mask(LOG_UNIMP, > "CXL 8 byte cache mem registers not implemented\n"); > > > > > > > > > > > --- > > > > v6: Initialize type variable to avoid a false compiler warning > > > > from some versions of gcc. (Michael Tsirkin) > > > > --- > > > > docs/system/devices/cxl.rst | 23 +++++ > > > > include/hw/cxl/cxl_component.h | 54 ++++++++++- > > > > include/hw/cxl/cxl_device.h | 3 + > > > > hw/cxl/cxl-component-utils.c | 142 ++++++++++++++++++++++++++-- > > > > hw/mem/cxl_type3.c | 9 +- > > > > hw/pci-bridge/cxl_downstream.c | 2 +- > > > > hw/pci-bridge/cxl_root_port.c | 3 +- > > > > hw/pci-bridge/cxl_upstream.c | 2 +- > > > > hw/pci-bridge/pci_expander_bridge.c | 2 +- > > > > 9 files changed, 225 insertions(+), 15 deletions(-) > > > > > > > > diff --git a/docs/system/devices/cxl.rst b/docs/system/devices/cxl.rst > > > > index ca15a0da1c1d..9d0771cdfd73 100644 > > > > --- a/docs/system/devices/cxl.rst > > > > +++ b/docs/system/devices/cxl.rst > > > > @@ -384,6 +384,29 @@ An example of 4 devices below a switch suitable for 1, 2 or 4 way interleave:: > > > > -device cxl-type3,bus=swport3,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem3,sn=0x4 \ > > > > -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=4k > > > > > > > > +An example of 4 type3 devices with volatile memory below a switch. Two of the devices > > > > +use HDM-DB for coherence, which requires operating in Flit mode:: > > > > + > > > > + qemu-system-x86_64 -M q35,cxl=on -m 4G,maxmem=8G,slots=8 -smp 4 \ > > > > + ... > > > > + -object memory-backend-ram,id=cxl-mem0,share=on,size=256M \ > > > > + -object memory-backend-ram,id=cxl-mem1,share=on,size=256M \ > > > > + -object memory-backend-ram,id=cxl-mem2,share=on,size=256M \ > > > > + -object memory-backend-ram,id=cxl-mem3,share=on,size=256M \ > > > > + -device pxb-cxl,bus_nr=12,bus=pcie.0,id=cxl.1 \ > > > > + -device cxl-rp,port=0,bus=cxl.1,id=root_port0,chassis=0,slot=0 \ > > > > + -device cxl-rp,port=1,bus=cxl.1,id=root_port1,chassis=0,slot=1 \ > > > > + -device cxl-upstream,bus=root_port0,id=us0,x-256b-flit=on \ > > > > + -device cxl-downstream,port=0,bus=us0,id=swport0,chassis=0,slot=4 \ > > > > + -device cxl-type3,bus=swport0,volatile-memdev=cxl-mem0,id=cxl-mem0,sn=0x1,x-256b-flit=on,hdm-db=on \ > > > > + -device cxl-downstream,port=1,bus=us0,id=swport1,chassis=0,slot=5 \ > > > > + -device cxl-type3,bus=swport1,volatile-memdev=cxl-mem1,id=cxl-mem1,sn=0x2,x-256b-flit=on,hdm-db=on \ > > > > + -device cxl-downstream,port=2,bus=us0,id=swport2,chassis=0,slot=6 \ > > > > + -device cxl-type3,bus=swport2,volatile-memdev=cxl-mem2,id=cxl-mem2,sn=0x3 \ > > > > + -device cxl-downstream,port=3,bus=us0,id=swport3,chassis=0,slot=7 \ > > > > + -device cxl-type3,bus=swport3,volatile-memdev=cxl-mem3,id=cxl-mem3,sn=0x4 \ > > > > + -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=4k > > > > + > > > > A simple arm/virt example featuring a single direct connected CXL Type 3 > > > > Volatile Memory device:: > > > > > > > > diff --git a/include/hw/cxl/cxl_component.h b/include/hw/cxl/cxl_component.h > > > > index 1f167d3ef79b..ffc82202206c 100644 > > > > --- a/include/hw/cxl/cxl_component.h > > > > +++ b/include/hw/cxl/cxl_component.h > > > > @@ -67,6 +67,8 @@ CXLx_CAPABILITY_HEADER(LINK, 2) > > > > CXLx_CAPABILITY_HEADER(HDM, 3) > > > > CXLx_CAPABILITY_HEADER(EXTSEC, 4) > > > > CXLx_CAPABILITY_HEADER(SNOOP, 5) > > > > +CXLx_CAPABILITY_HEADER(BI_RT, 6) > > > > +CXLx_CAPABILITY_HEADER(BI_DECODER, 7) > > > > > > > > /* > > > > * Capability structures contain the actual registers that the CXL component > > > > @@ -211,10 +213,55 @@ HDM_DECODER_INIT(3); > > > > (CXL_IDE_REGISTERS_OFFSET + CXL_IDE_REGISTERS_SIZE) > > > > #define CXL_SNOOP_REGISTERS_SIZE 0x8 > > > > > > > > -QEMU_BUILD_BUG_MSG((CXL_SNOOP_REGISTERS_OFFSET + > > > > - CXL_SNOOP_REGISTERS_SIZE) >= 0x1000, > > > > +#define CXL_BI_RT_CAP_VERSION 1 > > > > +#define CXL_BI_RT_REGISTERS_OFFSET \ > > > > + (CXL_SNOOP_REGISTERS_OFFSET + CXL_SNOOP_REGISTERS_SIZE) > > > > +#define CXL_BI_RT_REGISTERS_SIZE 0xC > > > > + > > > > +REG32(CXL_BI_RT_CAPABILITY, CXL_BI_RT_REGISTERS_OFFSET) > > > > + FIELD(CXL_BI_RT_CAPABILITY, EXPLICIT_COMMIT, 0, 1) > > > > +REG32(CXL_BI_RT_CTRL, CXL_BI_RT_REGISTERS_OFFSET + 0x4) > > > > + FIELD(CXL_BI_RT_CTRL, COMMIT, 0, 1) > > > > +REG32(CXL_BI_RT_STATUS, CXL_BI_RT_REGISTERS_OFFSET + 0x8) > > > > + FIELD(CXL_BI_RT_STATUS, COMMITTED, 0, 1) > > > > + FIELD(CXL_BI_RT_STATUS, ERR_NOT_COMMITTED, 1, 1) > > > > + FIELD(CXL_BI_RT_STATUS, COMMIT_TMO_SCALE, 8, 4) > > > > + FIELD(CXL_BI_RT_STATUS, COMMIT_TMO_BASE, 12, 4) > > > > + > > > > +/* CXL r3.2 8.2.4.27 - CXL BI Decoder Capability Structure */ > > > > +#define CXL_BI_DECODER_CAP_VERSION 1 > > > > +#define CXL_BI_DECODER_REGISTERS_OFFSET \ > > > > + (CXL_BI_RT_REGISTERS_OFFSET + CXL_BI_RT_REGISTERS_SIZE) > > > > +#define CXL_BI_DECODER_REGISTERS_SIZE 0xC > > > > + > > > > +REG32(CXL_BI_DECODER_CAPABILITY, CXL_BI_DECODER_REGISTERS_OFFSET) > > > > + FIELD(CXL_BI_DECODER_CAPABILITY, HDM_D, 0, 1) > > > > + FIELD(CXL_BI_DECODER_CAPABILITY, EXPLICIT_COMMIT, 1, 1) > > > > +REG32(CXL_BI_DECODER_CTRL, CXL_BI_DECODER_REGISTERS_OFFSET + 0x4) > > > > + FIELD(CXL_BI_DECODER_CTRL, BI_FW, 0, 1) > > > > + FIELD(CXL_BI_DECODER_CTRL, BI_ENABLE, 1, 1) > > > > + FIELD(CXL_BI_DECODER_CTRL, COMMIT, 2, 1) > > > > +REG32(CXL_BI_DECODER_STATUS, CXL_BI_DECODER_REGISTERS_OFFSET + 0x8) > > > > + FIELD(CXL_BI_DECODER_STATUS, COMMITTED, 0, 1) > > > > + FIELD(CXL_BI_DECODER_STATUS, ERR_NOT_COMMITTED, 1, 1) > > > > + FIELD(CXL_BI_DECODER_STATUS, COMMIT_TMO_SCALE, 8, 4) > > > > + FIELD(CXL_BI_DECODER_STATUS, COMMIT_TMO_BASE, 12, 4) > > > > + > > > > +QEMU_BUILD_BUG_MSG((CXL_BI_DECODER_REGISTERS_OFFSET + > > > > + CXL_BI_DECODER_REGISTERS_SIZE) >= 0x1000, > > > > "No space for registers"); > > > > > > > > +/* track BI explicit commit handling for route table and decoder */ > > > > +enum { > > > > + CXL_BISTATE_RT = 0, > > > > + CXL_BISTATE_DECODER, > > > > + CXL_BISTATE_MAX > > > > +}; > > > > + > > > > +typedef struct bi_state { > > > > + uint64_t last_commit; /* last 0->1 transition */ > > > > +} BIState; > > > > + > > > > typedef struct component_registers { > > > > /* > > > > * Main memory region to be registered with QEMU core. > > > > @@ -259,6 +306,7 @@ typedef struct cxl_component { > > > > }; > > > > > > > > CDATObject cdat; > > > > + BIState bi_state[CXL_BISTATE_MAX]; > > > > } CXLComponentState; > > > > > > > > void cxl_component_register_block_init(Object *obj, > > > > @@ -266,7 +314,7 @@ void cxl_component_register_block_init(Object *obj, > > > > const char *type); > > > > void cxl_component_register_init_common(uint32_t *reg_state, > > > > uint32_t *write_msk, > > > > - enum reg_type type); > > > > + enum reg_type type, bool bi); > > > > > > > > void cxl_component_create_dvsec(CXLComponentState *cxl_cstate, > > > > enum reg_type cxl_dev_type, uint16_t length, > > > > diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h > > > > index 7d9236db8c85..393f3122173b 100644 > > > > --- a/include/hw/cxl/cxl_device.h > > > > +++ b/include/hw/cxl/cxl_device.h > > > > @@ -770,6 +770,9 @@ struct CXLType3Dev { > > > > CXLMemSparingReadAttrs rank_sparing_attrs; > > > > CXLMemSparingWriteAttrs rank_sparing_wr_attrs; > > > > > > > > + /* BI flows */ > > > > + bool hdmdb; > > > > + > > > > struct dynamic_capacity { > > > > HostMemoryBackend *host_dc; > > > > AddressSpace host_dc_as; > > > > diff --git a/hw/cxl/cxl-component-utils.c b/hw/cxl/cxl-component-utils.c > > > > index 91770f103a85..a7d36e1128c2 100644 > > > > --- a/hw/cxl/cxl-component-utils.c > > > > +++ b/hw/cxl/cxl-component-utils.c > > > > @@ -71,10 +71,40 @@ static uint64_t cxl_cache_mem_read_reg(void *opaque, hwaddr offset, > > > > case 4: > > > > if (cregs->special_ops && cregs->special_ops->read) { > > > > return cregs->special_ops->read(cxl_cstate, offset, 4); > > > > - } else { > > > > - QEMU_BUILD_BUG_ON(sizeof(*cregs->cache_mem_registers) != 4); > > > > - return cregs->cache_mem_registers[offset / 4]; > > > > } > > > > + > > > > + QEMU_BUILD_BUG_ON(sizeof(*cregs->cache_mem_registers) != 4); > > > > + > > > > + if (offset == A_CXL_BI_RT_STATUS || > > > > + offset == A_CXL_BI_DECODER_STATUS) { > > > > + int type; > > > > + uint64_t started; > > > > + > > > > + type = (offset == A_CXL_BI_RT_STATUS) ? > > > > + CXL_BISTATE_RT : CXL_BISTATE_DECODER; > > > > + started = cxl_cstate->bi_state[type].last_commit; > > > > + > > > > + if (started) { > > > > + uint32_t *cache_mem = cregs->cache_mem_registers; > > > > + uint32_t val = cache_mem[offset / 4]; > > > > + uint64_t now; > > > > + int set; > > > > + > > > > + now = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL); > > > > + /* arbitrary 100 ms to do the commit */ > > > > + set = !!(now >= started + 100); > > > > + > > > > + if (offset == A_CXL_BI_RT_STATUS) { > > > > + val = FIELD_DP32(val, CXL_BI_RT_STATUS, COMMITTED, set); > > > > + } else { > > > > + val = FIELD_DP32(val, CXL_BI_DECODER_STATUS, COMMITTED, > > > > + set); > > > > + } > > > > + stl_le_p((uint8_t *)cache_mem + offset, val); > > > > + } > > > > + } > > > > + > > > > + return cregs->cache_mem_registers[offset / 4]; > > > > case 8: > > > > qemu_log_mask(LOG_UNIMP, > > > > "CXL 8 byte cache mem registers not implemented\n"); > > > > @@ -118,6 +148,47 @@ static void dumb_hdm_handler(CXLComponentState *cxl_cstate, hwaddr offset, > > > > stl_le_p((uint8_t *)cache_mem + offset, value); > > > > } > > > > > > > > +static void bi_handler(CXLComponentState *cxl_cstate, hwaddr offset, > > > > + uint32_t value) > > > > +{ > > > > + ComponentRegisters *cregs = &cxl_cstate->crb; > > > > + uint32_t sts, *cache_mem = cregs->cache_mem_registers; > > > > + bool to_commit = false; > > > > + int type = 0; /* Unused value - work around for compiler warning */ > > > > + > > > > + switch (offset) { > > > > + case A_CXL_BI_RT_CTRL: > > > > + to_commit = FIELD_EX32(value, CXL_BI_RT_CTRL, COMMIT); > > > > + if (to_commit) { > > > > + sts = cxl_cache_mem_read_reg(cxl_cstate, > > > > + R_CXL_BI_RT_STATUS, 4); > > > > + sts = FIELD_DP32(sts, CXL_BI_RT_STATUS, COMMITTED, 0); > > > > + stl_le_p((uint8_t *)cache_mem + R_CXL_BI_RT_STATUS, sts); > > > > + type = CXL_BISTATE_RT; > > > > + } > > > > + break; > > > > + case A_CXL_BI_DECODER_CTRL: > > > > + to_commit = FIELD_EX32(value, CXL_BI_DECODER_CTRL, COMMIT); > > > > + if (to_commit) { > > > > + sts = cxl_cache_mem_read_reg(cxl_cstate, > > > > + R_CXL_BI_DECODER_STATUS, 4); > > > > + sts = FIELD_DP32(sts, CXL_BI_DECODER_STATUS, COMMITTED, 0); > > > > + stl_le_p((uint8_t *)cache_mem + R_CXL_BI_DECODER_STATUS, sts); > > > > + type = CXL_BISTATE_DECODER; > > > > + } > > > > + break; > > > > + default: > > > > + break; > > > > + } > > > > + > > > > + if (to_commit) { > > > > + cxl_cstate->bi_state[type].last_commit = > > > > + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL); > > > > + } > > > > + > > > > + stl_le_p((uint8_t *)cache_mem + offset, value); > > > > +} > > > > + > > > > static void cxl_cache_mem_write_reg(void *opaque, hwaddr offset, uint64_t value, > > > > unsigned size) > > > > { > > > > @@ -141,6 +212,9 @@ static void cxl_cache_mem_write_reg(void *opaque, hwaddr offset, uint64_t value, > > > > if (offset >= A_CXL_HDM_DECODER_CAPABILITY && > > > > offset <= A_CXL_HDM_DECODER3_TARGET_LIST_HI) { > > > > dumb_hdm_handler(cxl_cstate, offset, value); > > > > + } else if (offset == A_CXL_BI_RT_CTRL || > > > > + offset == A_CXL_BI_DECODER_CTRL) { > > > > + bi_handler(cxl_cstate, offset, value); > > > > } else { > > > > cregs->cache_mem_registers[offset / 4] = value; > > > > } > > > > @@ -230,7 +304,7 @@ static void ras_init_common(uint32_t *reg_state, uint32_t *write_msk) > > > > } > > > > > > > > static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk, > > > > - enum reg_type type) > > > > + enum reg_type type, bool bi) > > > > { > > > > int decoder_count = CXL_HDM_DECODER_COUNT; > > > > int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO; > > > > @@ -255,7 +329,9 @@ static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk, > > > > UIO_DECODER_COUNT, 0); > > > > ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, MEMDATA_NXM_CAP, 0); > > > > ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, > > > > - SUPPORTED_COHERENCY_MODEL, 0); /* Unknown */ > > > > + SUPPORTED_COHERENCY_MODEL, > > > > + /* host+dev or Unknown */ > > > > + type == CXL2_TYPE3_DEVICE && bi ? 3 : 0); > > > > ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_GLOBAL_CONTROL, > > > > HDM_DECODER_ENABLE, 0); > > > > write_msk[R_CXL_HDM_DECODER_GLOBAL_CONTROL] = 0x3; > > > > @@ -278,9 +354,43 @@ static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk, > > > > } > > > > } > > > > > > > > +static void bi_rt_init_common(uint32_t *reg_state, uint32_t *write_msk) > > > > +{ > > > > + /* switch usp must commit the new BI-ID, timeout of 2secs */ > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_RT_CAPABILITY, EXPLICIT_COMMIT, 1); > > > > + > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_RT_CTRL, COMMIT, 0); > > > > + write_msk[R_CXL_BI_RT_CTRL] = 0x1; > > > > + > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_RT_STATUS, COMMITTED, 0); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_RT_STATUS, ERR_NOT_COMMITTED, 0); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_RT_STATUS, COMMIT_TMO_SCALE, 0x6); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_RT_STATUS, COMMIT_TMO_BASE, 0x2); > > > > +} > > > > + > > > > +static void bi_decoder_init_common(uint32_t *reg_state, uint32_t *write_msk, > > > > + enum reg_type type) > > > > +{ > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_CAPABILITY, HDM_D, 0); > > > > + /* switch dsp must commit the new BI-ID, timeout of 2secs */ > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_CAPABILITY, EXPLICIT_COMMIT, > > > > + (type != CXL2_ROOT_PORT && type != CXL2_TYPE3_DEVICE)); > > > > + > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_CTRL, BI_FW, 0); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_CTRL, BI_ENABLE, 0); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_CTRL, COMMIT, 0); > > > > + write_msk[R_CXL_BI_DECODER_CTRL] = 0x7; > > > > + > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_STATUS, COMMITTED, 0); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_STATUS, ERR_NOT_COMMITTED, 0); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_STATUS, COMMIT_TMO_SCALE, 0x6); > > > > + ARRAY_FIELD_DP32(reg_state, CXL_BI_DECODER_STATUS, COMMIT_TMO_BASE, 0x2); > > > > +} > > > > + > > > > void cxl_component_register_init_common(uint32_t *reg_state, > > > > uint32_t *write_msk, > > > > - enum reg_type type) > > > > + enum reg_type type, > > > > + bool bi) > > > > { > > > > int caps = 0; > > > > > > > > @@ -320,7 +430,7 @@ void cxl_component_register_init_common(uint32_t *reg_state, > > > > case CXL2_LOGICAL_DEVICE: > > > > /* + HDM */ > > > > init_cap_reg(HDM, 5, 1); > > > > - hdm_init_common(reg_state, write_msk, type); > > > > + hdm_init_common(reg_state, write_msk, type, bi); > > > > /* fallthrough */ > > > > case CXL2_DOWNSTREAM_PORT: > > > > case CXL2_DEVICE: > > > > @@ -335,6 +445,24 @@ void cxl_component_register_init_common(uint32_t *reg_state, > > > > abort(); > > > > } > > > > > > > > + /* back invalidate */ > > > > + if (bi) { > > > > + switch (type) { > > > > + case CXL2_UPSTREAM_PORT: > > > > + init_cap_reg(BI_RT, 11, CXL_BI_RT_CAP_VERSION); > > > > + bi_rt_init_common(reg_state, write_msk); > > > > + break; > > > > + case CXL2_ROOT_PORT: > > > > + case CXL2_DOWNSTREAM_PORT: > > > > + case CXL2_TYPE3_DEVICE: > > > > + init_cap_reg(BI_DECODER, 12, CXL_BI_DECODER_CAP_VERSION); > > > > + bi_decoder_init_common(reg_state, write_msk, type); > > > > + break; > > > > + default: > > > > + break; > > > > + } > > > > + } > > > > + > > > > ARRAY_FIELD_DP32(reg_state, CXL_CAPABILITY_HEADER, ARRAY_SIZE, caps); > > > > #undef init_cap_reg > > > > } > > > > diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c > > > > index 3c7ecd8c48bc..3f09c589ae58 100644 > > > > --- a/hw/mem/cxl_type3.c > > > > +++ b/hw/mem/cxl_type3.c > > > > @@ -748,6 +748,11 @@ static bool cxl_setup_memory(CXLType3Dev *ct3d, Error **errp) > > > > return false; > > > > } > > > > > > > > + if (!ct3d->flitmode && ct3d->hdmdb) { > > > > + error_setg(errp, "hdm-db requires operating in 256b flit"); > > > > + return false; > > > > + } > > > > + > > > > if (ct3d->hostvmem) { > > > > MemoryRegion *vmr; > > > > char *v_name; > > > > @@ -1317,7 +1322,8 @@ static void ct3d_reset(DeviceState *dev) > > > > > > > > pcie_cap_fill_link_ep_usp(PCI_DEVICE(dev), ct3d->width, ct3d->speed, > > > > ct3d->flitmode); > > > > - cxl_component_register_init_common(reg_state, write_msk, CXL2_TYPE3_DEVICE); > > > > + cxl_component_register_init_common(reg_state, write_msk, > > > > + CXL2_TYPE3_DEVICE, ct3d->hdmdb); > > > > cxl_device_register_init_t3(ct3d, CXL_T3_MSIX_MBOX); > > > > > > > > /* > > > > @@ -1356,6 +1362,7 @@ static const Property ct3_props[] = { > > > > DEFINE_PROP_PCIE_LINK_WIDTH("x-width", CXLType3Dev, > > > > width, PCIE_LINK_WIDTH_16), > > > > DEFINE_PROP_BOOL("x-256b-flit", CXLType3Dev, flitmode, false), > > > > + DEFINE_PROP_BOOL("hdm-db", CXLType3Dev, hdmdb, false), > > > > }; > > > > > > > > static uint64_t get_lsa_size(CXLType3Dev *ct3d) > > > > diff --git a/hw/pci-bridge/cxl_downstream.c b/hw/pci-bridge/cxl_downstream.c > > > > index 64086d8ec2f2..320818a8f1ce 100644 > > > > --- a/hw/pci-bridge/cxl_downstream.c > > > > +++ b/hw/pci-bridge/cxl_downstream.c > > > > @@ -39,7 +39,7 @@ static void latch_registers(CXLDownstreamPort *dsp) > > > > uint32_t *write_msk = dsp->cxl_cstate.crb.cache_mem_regs_write_mask; > > > > > > > > cxl_component_register_init_common(reg_state, write_msk, > > > > - CXL2_DOWNSTREAM_PORT); > > > > + CXL2_DOWNSTREAM_PORT, true); > > > > } > > > > > > > > /* TODO: Look at sharing this code across all CXL port types */ > > > > diff --git a/hw/pci-bridge/cxl_root_port.c b/hw/pci-bridge/cxl_root_port.c > > > > index 5641048084a4..e2093ac39ee6 100644 > > > > --- a/hw/pci-bridge/cxl_root_port.c > > > > +++ b/hw/pci-bridge/cxl_root_port.c > > > > @@ -101,7 +101,8 @@ static void latch_registers(CXLRootPort *crp) > > > > uint32_t *reg_state = crp->cxl_cstate.crb.cache_mem_registers; > > > > uint32_t *write_msk = crp->cxl_cstate.crb.cache_mem_regs_write_mask; > > > > > > > > - cxl_component_register_init_common(reg_state, write_msk, CXL2_ROOT_PORT); > > > > + cxl_component_register_init_common(reg_state, write_msk, CXL2_ROOT_PORT, > > > > + true); > > > > } > > > > > > > > static void build_dvsecs(PCIDevice *d, CXLComponentState *cxl) > > > > diff --git a/hw/pci-bridge/cxl_upstream.c b/hw/pci-bridge/cxl_upstream.c > > > > index c352d11dc7b7..fb8d19539c9f 100644 > > > > --- a/hw/pci-bridge/cxl_upstream.c > > > > +++ b/hw/pci-bridge/cxl_upstream.c > > > > @@ -90,7 +90,7 @@ static void latch_registers(CXLUpstreamPort *usp) > > > > uint32_t *write_msk = usp->cxl_cstate.crb.cache_mem_regs_write_mask; > > > > > > > > cxl_component_register_init_common(reg_state, write_msk, > > > > - CXL2_UPSTREAM_PORT); > > > > + CXL2_UPSTREAM_PORT, usp->flitmode); > > > > ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, TARGET_COUNT, 8); > > > > } > > > > > > > > diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c > > > > index b6e2eb796951..11623a5666f6 100644 > > > > --- a/hw/pci-bridge/pci_expander_bridge.c > > > > +++ b/hw/pci-bridge/pci_expander_bridge.c > > > > @@ -300,7 +300,7 @@ static void pxb_cxl_dev_reset(DeviceState *dev) > > > > uint32_t *write_msk = cxl_cstate->crb.cache_mem_regs_write_mask; > > > > int dsp_count = 0; > > > > > > > > - cxl_component_register_init_common(reg_state, write_msk, CXL2_RC); > > > > + cxl_component_register_init_common(reg_state, write_msk, CXL2_RC, false); > > > > /* > > > > * The CXL specification allows for host bridges with no HDM decoders > > > > * if they only have a single root port. > > > > -- > > > > 2.51.0 > > > >