On Thu, May 22, 2025 at 12:01:35PM +0530, Vinayak Holikatti wrote:
> CXL spec 3.2 section 7.6.7.5.2 describes Get Head Info.
>
> Signed-off-by: Vinayak Holikatti <vinayak...@samsung.com>
> ---
> This patch is generated against Jonathan Cameron's branch cxl-2025-03-20
>
> hw/cxl/cxl-mailbox-utils.c | 21 +++++++++
> hw/cxl/mhsld/mhsld.c | 92 ++++++++++++++++++++++++++++++++++++-
> hw/cxl/mhsld/mhsld.h | 26 +++++++++++
> include/hw/cxl/cxl_device.h | 6 +++
> 4 files changed, 144 insertions(+), 1 deletion(-)
>
> diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> index a02d130926..4f25caecea 100644
> --- a/hw/cxl/cxl-mailbox-utils.c
> +++ b/hw/cxl/cxl-mailbox-utils.c
> @@ -122,6 +122,7 @@ enum {
> #define MANAGEMENT_COMMAND 0x0
> MHD = 0x55,
> #define GET_MHD_INFO 0x0
> + #define GET_MHD_HEAD_INFO 0x1
> };
>
> /* CCI Message Format CXL r3.1 Figure 7-19 */
> @@ -267,6 +268,23 @@ static CXLRetCode cmd_mhd_get_info(const struct cxl_cmd
> *cmd,
> return CXL_MBOX_UNSUPPORTED;
> }
>
> +/*
> + * CXL r3.2 section 7.6.7.5.2 - Get Multi-Headed Head Info (Opcode 5501h)
That does not match the section subject of the spec
Get Head Info (...
> + */
> +static CXLRetCode cmd_mhd_get_head_info(const struct cxl_cmd *cmd,
> + uint8_t *payload_in, size_t len_in,
> + uint8_t *payload_out, size_t *len_out,
> + CXLCCI *cci)
The indent here is not right.
> +static CXLRetCode cmd_mhd_get_head_info(const struct cxl_cmd *cmd,
> + uint8_t *payload_in, size_t len_in,
> +{
> + CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
> + CXLType3Class *cvc = CXL_TYPE3_GET_CLASS(ct3d);
> + if (cvc->mhd_get_head_info) {
> + return cvc->mhd_get_head_info(cmd, payload_in, len_in, payload_out,
> + len_out, cci);
indent needs fix.
> + }
> + return CXL_MBOX_UNSUPPORTED;
> +}
> +
> static CXLRetCode cmd_events_get_records(const struct cxl_cmd *cmd,
> uint8_t *payload_in, size_t len_in,
> uint8_t *payload_out, size_t
> *len_out,
> @@ -3429,6 +3447,7 @@ static const struct cxl_cmd cxl_cmd_set[256][256] = {
> "MEDIA_AND_POISON_GET_SCAN_MEDIA_RESULTS",
> cmd_media_get_scan_media_results, 0, 0 },
> [MHD][GET_MHD_INFO] = { "GET_MULTI_HEADED_INFO", cmd_mhd_get_info, 2, 0},
> + [MHD][GET_MHD_HEAD_INFO] = { "GET_MULTI_HEADED_INFO",
> cmd_mhd_get_head_info, 2, 0},
> };
>
> static const struct cxl_cmd cxl_cmd_set_dcd[256][256] = {
> @@ -3761,6 +3780,8 @@ static const struct cxl_cmd
> cxl_cmd_set_t3_fm_owned_ld_mctp[256][256] = {
> [TIMESTAMP][GET] = { "TIMESTAMP_GET", cmd_timestamp_get, 0, 0 },
> [TUNNEL][MANAGEMENT_COMMAND] = { "TUNNEL_MANAGEMENT_COMMAND",
> cmd_tunnel_management_cmd, ~0, 0 },
> + [MHD][GET_MHD_INFO] = { "GET_MULTI_HEADED_INFO", cmd_mhd_get_info, 2, 0},
> + [MHD][GET_MHD_HEAD_INFO] = { "GET_MULTI_HEADED_INFO",
> cmd_mhd_get_head_info, 2, 0},
> };
>
> void cxl_initialize_t3_fm_owned_ld_mctpcci(CXLCCI *cci, DeviceState *d,
> diff --git a/hw/cxl/mhsld/mhsld.c b/hw/cxl/mhsld/mhsld.c
> index 9f633b3bed..981546b5ff 100644
> --- a/hw/cxl/mhsld/mhsld.c
> +++ b/hw/cxl/mhsld/mhsld.c
> @@ -61,9 +61,57 @@ static CXLRetCode cmd_mhd_get_info(const struct cxl_cmd
> *cmd,
> return CXL_MBOX_SUCCESS;
> }
>
> +/*
> + * CXL r3.2 section 7.6.7.5.2 - Get Head Info (Opcode 5501h)
> + *
> + * This command retrieves the number of heads, number of supported LDs,
> + * and Head-to-LD mapping of a Multi-Headed device.
> + */
> +static CXLRetCode cmd_mhd_get_head_info(const struct cxl_cmd *cmd,
> + uint8_t *payload_in, size_t len_in,
> + uint8_t *payload_out, size_t
> *len_out,
> + CXLCCI *cci)
> +{
> + CXLMHSLDState *s = CXL_MHSLD(cci->d);
> + MHDGetHeadInfoInput *input = (void *)payload_in;
> + MHDGetHeadInfoOutput *output = (void *)payload_out;
> + int i = 0;
> +
> + if (input->start_head > MHSLD_HEADS) {
Should be ">=" ?
Also, per the spec, we need also check the "number of heads" field, if
start_head and number of heads together point to a non-exist head, we
should return invalid input.
> + return CXL_MBOX_INVALID_INPUT;
> + }
> +
> + output->nr_heads = MIN((MHSLD_HEADS - input->start_head),
> input->nr_heads);
> + for (i = input->start_head; i < input->start_head + output->nr_heads;
> i++) {
> + output->head_info_list[i].port_number =
> +
> s->mhd_state->head_info_blocks[i].port_number;
> + output->head_info_list[i].max_link_width =
> +
> s->mhd_state->head_info_blocks[i].max_link_width;
> + output->head_info_list[i].nego_link_width =
> +
> s->mhd_state->head_info_blocks[i].nego_link_width;
> + output->head_info_list[i].supp_link_speeds_vector =
> +
> s->mhd_state->head_info_blocks[i].supp_link_speeds_vector;
> + output->head_info_list[i].max_link_speed =
> +
> s->mhd_state->head_info_blocks[i].max_link_speed;
> + output->head_info_list[i].current_link_speed =
> +
> s->mhd_state->head_info_blocks[i].current_link_speed;
> + output->head_info_list[i].ltssm_state =
> +
> s->mhd_state->head_info_blocks[i].ltssm_state;
> + output->head_info_list[i].first_nego_lane_num =
> +
> s->mhd_state->head_info_blocks[i].first_nego_lane_num;
> + output->head_info_list[i].link_state_flags =
> +
> s->mhd_state->head_info_blocks[i].link_state_flags;
> + }
> +
> + *len_out = sizeof(*output) + output->nr_heads * sizeof(MHDHeadInfoBlock);
> + return CXL_MBOX_SUCCESS;
> +}
> +
> static const struct cxl_cmd cxl_cmd_set_mhsld[256][256] = {
> [MHSLD_MHD][GET_MHD_INFO] = {"GET_MULTI_HEADED_INFO",
> cmd_mhd_get_info, 2, 0},
> + [MHSLD_MHD][GET_MHD_HEAD_INFO] = {"GET_HEAD_INFO",
> + cmd_mhd_get_head_info, 2, 0},
> };
>
> static const Property cxl_mhsld_props[] = {
> @@ -166,6 +214,47 @@ static void cxl_mhsld_state_initialize(CXLMHSLDState *s,
> size_t dc_size)
> s->mhd_state->nr_blocks = dc_size / MHSLD_BLOCK_SZ;
> }
>
> +
> +static void cxl_mhsld_init_head_info(CXLMHSLDState *s, PCIDevice *pdev)
> +{
> + uint16_t lnksta = 0;
> + uint16_t current_link_speed = 0;
> + uint16_t negotiated_link_width = 0;
> + uint16_t lnkcap = 0, lnkcap2 = 0;
> + uint16_t max_link_width = 0;
> + uint16_t max_link_speed = 0;
> + uint16_t supported_link_speeds_vector = 0;
> +
> + lnksta = pdev->config_read(pdev,
> + pdev->exp.exp_cap + PCI_EXP_LNKSTA,
> + sizeof(lnksta));
> + lnkcap = pdev->config_read(pdev,
> + pdev->exp.exp_cap + PCI_EXP_LNKCAP,
> + sizeof(lnkcap));
> + lnkcap2 = pdev->config_read(pdev,
> + pdev->exp.exp_cap + PCI_EXP_LNKCAP2,
> + sizeof(lnkcap2));
> + supported_link_speeds_vector = (lnkcap2 & 0xFE) >> 1;
> + max_link_width = (lnkcap & PCI_EXP_LNKCAP_MLW) >> 4;
> + max_link_speed = lnkcap & PCI_EXP_LNKCAP_SLS;
> + current_link_speed = lnksta & PCI_EXP_LNKSTA_CLS;
> + negotiated_link_width = (lnksta & PCI_EXP_LNKSTA_NLW) >> 4;
> +
> + s->mhd_state->head_info_blocks[s->mhd_head].port_number = s->mhd_head;
> + s->mhd_state->head_info_blocks[s->mhd_head].max_link_width =
> max_link_width;
> + s->mhd_state->head_info_blocks[s->mhd_head].nego_link_width =
> +
> negotiated_link_width;
> + s->mhd_state->head_info_blocks[s->mhd_head].supp_link_speeds_vector =
> +
> supported_link_speeds_vector;
> + s->mhd_state->head_info_blocks[s->mhd_head].max_link_speed =
> +
> max_link_speed;
> + s->mhd_state->head_info_blocks[s->mhd_head].current_link_speed =
> +
> current_link_speed;
> + s->mhd_state->head_info_blocks[s->mhd_head].ltssm_state = 0x7;
> + s->mhd_state->head_info_blocks[s->mhd_head].first_nego_lane_num = 0;
> + s->mhd_state->head_info_blocks[s->mhd_head].link_state_flags = 0;
> +}
> +
> /* Returns starting index of region in MHD map. */
> static inline size_t cxl_mhsld_find_dc_region_start(PCIDevice *d,
> CXLDCRegion *r)
> @@ -376,7 +465,7 @@ static void cxl_mhsld_realize(PCIDevice *pci_dev, Error
> **errp)
> }
>
> cxl_mhsld_state_initialize(s, dc_size);
> -
> + cxl_mhsld_init_head_info(s, pci_dev);
> /* Set the LD ownership for this head to this system */
> s->mhd_state->ldmap[s->mhd_head] = s->mhd_head;
> return;
> @@ -428,6 +517,7 @@ static void cxl_mhsld_class_init(ObjectClass *klass, void
> *data)
>
> CXLType3Class *cvc = CXL_TYPE3_CLASS(klass);
> cvc->mhd_get_info = cmd_mhd_get_info;
> + cvc->mhd_get_head_info = cmd_mhd_get_head_info;
> cvc->mhd_access_valid = cxl_mhsld_access_valid;
> cvc->mhd_reserve_extents = cxl_mhsld_reserve_extents;
> cvc->mhd_reclaim_extents = cxl_mhsld_reclaim_extents;
> diff --git a/hw/cxl/mhsld/mhsld.h b/hw/cxl/mhsld/mhsld.h
> index e7ead1f0d2..c9fbec71ca 100644
> --- a/hw/cxl/mhsld/mhsld.h
> +++ b/hw/cxl/mhsld/mhsld.h
> @@ -23,6 +23,18 @@
> */
> #define MHSLD_HEADS (8)
>
> +typedef struct MHDHeadInfoBlock {
> + uint8_t port_number;
> + uint8_t max_link_width;
> + uint8_t nego_link_width;
> + uint8_t supp_link_speeds_vector;
> + uint8_t max_link_speed;
> + uint8_t current_link_speed;
> + uint8_t ltssm_state;
> + uint8_t first_nego_lane_num;
> + uint8_t link_state_flags;
> +} QEMU_PACKED MHDHeadInfoBlock;
> +
> /*
> * The shared state cannot have 2 variable sized regions
> * so we have to max out the ldmap.
> @@ -32,6 +44,7 @@ typedef struct MHSLDSharedState {
> uint8_t nr_lds;
> uint8_t ldmap[MHSLD_HEADS];
> uint64_t nr_blocks;
> + MHDHeadInfoBlock head_info_blocks[MHSLD_HEADS];
> uint8_t blocks[];
> } MHSLDSharedState;
>
> @@ -52,6 +65,7 @@ struct CXLMHSLDClass {
> enum {
> MHSLD_MHD = 0x55,
> #define GET_MHD_INFO 0x0
> + #define GET_MHD_HEAD_INFO 0x1
> };
>
> /*
> @@ -72,4 +86,16 @@ typedef struct MHDGetInfoOutput {
> uint16_t resv2;
> uint8_t ldmap[];
> } QEMU_PACKED MHDGetInfoOutput;
> +
> +typedef struct MHDGetHeadInfoInput {
> + uint8_t start_head;
> + uint8_t nr_heads;
> +} QEMU_PACKED MHDGetHeadInfoInput;
> +
> +typedef struct MHDGetHeadInfoOutput {
> + uint8_t nr_heads;
> + uint8_t rsvd[3];
> + MHDHeadInfoBlock head_info_list[];
s/head_info_list/head_info/
Fan
> +} QEMU_PACKED MHDGetHeadInfoOutput;
> +
> #endif
> diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
> index ca515cab13..c93c71c45d 100644
> --- a/include/hw/cxl/cxl_device.h
> +++ b/include/hw/cxl/cxl_device.h
> @@ -732,6 +732,12 @@ struct CXLType3Class {
> uint8_t *payload_out,
> size_t *len_out,
> CXLCCI *cci);
> + CXLRetCode (*mhd_get_head_info)(const struct cxl_cmd *cmd,
> + uint8_t *payload_in,
> + size_t len_in,
> + uint8_t *payload_out,
> + size_t *len_out,
> + CXLCCI *cci);
> bool (*mhd_access_valid)(PCIDevice *d, uint64_t addr, unsigned int size);
> bool (*mhd_reserve_extents)(PCIDevice *d,
> CxlDynamicCapacityExtentList *records,
> --
> 2.34.1
>
