Skip to content

Commit

Permalink
peci: mctp: Extract communication with MCTP
Browse files Browse the repository at this point in the history 
Right now, send and receive API functions are called directly from xfer
handler. Let's add a dedicated helper function responsible for
send/receive to allow issuing PECI messages originated in peci-mctp
driver.

Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com>
  • Loading branch information
@iklimasz @jaehyoo
iklimasz authored and jaehyoo committed Nov 5, 2021
1 parent a0212e9 commit 6538edd
Showing 1 changed file with 80 additions and 62 deletions.
142 changes: 80 additions & 62 deletions drivers/peci/busses/peci-mctp.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -61,41 +61,21 @@ static const struct mctp_peci_vdm_hdr peci_hdr_template = {
#define PECI_VDM_TYPE 0x0200
#define PECI_VDM_MASK 0xff00

struct node_cfg {
u8 eid;
u16 bdf;
};

struct mctp_peci {
struct peci_adapter *adapter;
struct device *dev;
struct mctp_client *peci_client;
u8 tag;
};

static int mctp_peci_get_address(u8 peci_addr, u8 *eid, u16 *bdf)
{
/*
* TODO: This is just a temporary hack to enable PECI over MCTP on
* platforms with 2 sockets.
* We are only able to hardcode MCTP endpoints and BDFs for CPU 0 and
* CPU 1. To support all CPUs, we need to add resolving CPU ID and
* endpoint ID.
*/
switch (peci_addr) {
case 0x30:
*eid = 0x1d;
*bdf = 0x6a18;
break;
case 0x31:
*eid = 0x3d;
*bdf = 0xe818;
break;
default:
return -EINVAL;
}

return 0;
}

static void prepare_tx_packet(struct mctp_pcie_packet *tx_packet,
struct peci_xfer_msg *msg, u8 eid,
u16 bdf, u8 tag)
static void
prepare_tx_packet(struct mctp_pcie_packet *tx_packet, struct node_cfg *cpu,
u8 tx_len, u8 rx_len, u8 *tx_buf, u8 tag)
{
struct pcie_transport_hdr *pcie_hdr;
struct mctp_protocol_hdr *mctp_hdr;
Expand All @@ -116,29 +96,29 @@ static void prepare_tx_packet(struct mctp_pcie_packet *tx_packet,
*peci_hdr = peci_hdr_template;

peci_payload = (u8 *)(tx_packet->data.payload) + sizeof(struct mctp_peci_vdm_hdr);
peci_payload[0] = msg->tx_len;
peci_payload[1] = msg->rx_len;
memcpy(&peci_payload[2], msg->tx_buf, msg->tx_len);
peci_payload[0] = tx_len;
peci_payload[1] = rx_len;
memcpy(&peci_payload[2], tx_buf, tx_len);

/*
* MCTP packet payload consists of PECI VDM header, WL, RL and actual
* PECI payload
*/
payload_len = sizeof(struct mctp_peci_vdm_hdr) + 2 + msg->tx_len;
payload_len = sizeof(struct mctp_peci_vdm_hdr) + 2 + tx_len;
payload_len_dw = PCIE_PKT_ALIGN(payload_len) / sizeof(u32);

PCIE_SET_DATA_LEN(pcie_hdr, payload_len_dw);

tx_packet->size = PCIE_PKT_ALIGN(payload_len) + PCIE_VDM_HDR_SIZE;

mctp_hdr->dest = eid;
PCIE_SET_TARGET_ID(pcie_hdr, bdf);
mctp_hdr->dest = cpu->eid;
PCIE_SET_TARGET_ID(pcie_hdr, cpu->bdf);
MCTP_SET_MSG_TAG(mctp_hdr, tag);
}

static int
verify_rx_packet(struct peci_adapter *adapter, struct mctp_pcie_packet *rx_packet,
u8 eid, u16 bdf, u8 tag)
struct node_cfg *cpu, u8 tag)
{
struct mctp_peci *priv = peci_get_adapdata(adapter);
bool invalid_packet = false;
Expand All @@ -156,16 +136,16 @@ verify_rx_packet(struct peci_adapter *adapter, struct mctp_pcie_packet *rx_packe

requester_id = PCIE_GET_REQUESTER_ID(pcie_hdr);

if (requester_id != bdf) {
if (requester_id != cpu->bdf) {
dev_dbg(priv->dev,
"mismatch in src bdf: expected: 0x%.4x, got: 0x%.4x",
bdf, requester_id);
cpu->bdf, requester_id);
invalid_packet = true;
}
if (mctp_hdr->src != eid) {
if (mctp_hdr->src != cpu->eid) {
dev_dbg(priv->dev,
"mismatch in src eid: expected: 0x%.2x, got: 0x%.2x",
eid, mctp_hdr->src);
cpu->eid, mctp_hdr->src);
invalid_packet = true;
}
if (mctp_hdr->flags_seq_tag != expected_flags) {
Expand All @@ -189,41 +169,31 @@ verify_rx_packet(struct peci_adapter *adapter, struct mctp_pcie_packet *rx_packe
return 0;
}

static int
mctp_peci_xfer(struct peci_adapter *adapter, struct peci_xfer_msg *msg)
static struct mctp_pcie_packet *
mctp_peci_send_receive(struct peci_adapter *adapter, struct node_cfg *cpu,
u8 tx_len, u8 rx_len, u8 *tx_buf)
{
struct mctp_peci *priv = peci_get_adapdata(adapter);
/* XXX: Sporadically it can take up to 1100 ms for response to arrive */
unsigned long timeout = msecs_to_jiffies(1100);
u32 max_len = sizeof(struct mctp_pcie_packet_data) -
PCIE_VDM_HDR_SIZE - sizeof(struct mctp_peci_vdm_hdr);
u8 tag = priv->tag;
struct mctp_pcie_packet *tx_packet, *rx_packet;
unsigned long current_time, end_time;
int ret;
u16 bdf;
u8 eid;

if (msg->tx_len > max_len || msg->rx_len > max_len)
return -EINVAL;

ret = mctp_peci_get_address(msg->addr, &eid, &bdf);
if (ret)
return ret;

tx_packet = aspeed_mctp_packet_alloc(GFP_KERNEL);
if (!tx_packet)
return -ENOMEM;
return ERR_PTR(-ENOMEM);

prepare_tx_packet(tx_packet, msg, eid, bdf, tag);
prepare_tx_packet(tx_packet, cpu, tx_len, rx_len, tx_buf, tag);

aspeed_mctp_flush_rx_queue(priv->peci_client);

ret = aspeed_mctp_send_packet(priv->peci_client, tx_packet);
if (ret) {
dev_dbg_ratelimited(priv->dev, "failed to send mctp packet: %d\n", ret);
aspeed_mctp_packet_free(tx_packet);
return ret;
return ERR_PTR(ret);
}
priv->tag++;

Expand All @@ -235,26 +205,74 @@ mctp_peci_xfer(struct peci_adapter *adapter, struct peci_xfer_msg *msg)
dev_err_ratelimited(priv->dev, "failed to receive mctp packet: %ld\n",
PTR_ERR(rx_packet));

return PTR_ERR(rx_packet);
return rx_packet;
}
BUG_ON(!rx_packet);

ret = verify_rx_packet(adapter, rx_packet, eid, bdf, tag);
ret = verify_rx_packet(adapter, rx_packet, cpu, tag);
current_time = jiffies;
if (ret && time_before(current_time, end_time)) {
aspeed_mctp_packet_free(rx_packet);
timeout = ((long)end_time - (long)current_time);
goto retry;
}

if (!ret)
memcpy(msg->rx_buf,
(u8 *)(rx_packet->data.payload) + sizeof(struct mctp_peci_vdm_hdr),
msg->rx_len);
return rx_packet;
}

static int
mctp_peci_get_address(struct peci_adapter *adapter, u8 peci_addr, struct node_cfg *cpu)
{
/*
* TODO: This is just a temporary hack to enable PECI over MCTP on
* platforms with 2 sockets.
* We are only able to hardcode MCTP endpoints and BDFs for CPU 0 and
* CPU 1. To support all CPUs, we need to add resolving CPU ID and
* endpoint ID.
*/
switch (peci_addr) {
case 0x30:
cpu->eid = 0x1d;
cpu->bdf = 0x6a18;
break;
case 0x31:
cpu->eid = 0x3d;
cpu->bdf = 0xe818;
break;
default:
return -EINVAL;
}

return 0;
}

static int
mctp_peci_xfer(struct peci_adapter *adapter, struct peci_xfer_msg *msg)
{
u32 max_len = sizeof(struct mctp_pcie_packet_data) -
PCIE_VDM_HDR_SIZE - sizeof(struct mctp_peci_vdm_hdr);
struct mctp_pcie_packet *rx_packet;
struct node_cfg cpu;
int ret;

if (msg->tx_len > max_len || msg->rx_len > max_len)
return -EINVAL;

ret = mctp_peci_get_address(adapter, msg->addr, &cpu);
if (ret)
return ret;

rx_packet = mctp_peci_send_receive(adapter, &cpu, msg->tx_len, msg->rx_len, msg->tx_buf);
if (IS_ERR(rx_packet))
return PTR_ERR(rx_packet);

memcpy(msg->rx_buf,
(u8 *)(rx_packet->data.payload) + sizeof(struct mctp_peci_vdm_hdr),
msg->rx_len);

aspeed_mctp_packet_free(rx_packet);

return ret;
return 0;
}

static int mctp_peci_init_peci_client(struct mctp_peci *priv)
Expand Down

0 comments on commit 6538edd

Please sign in to comment.