From 3df54c870f52b4c47b53eead8d22a109f741b91c Mon Sep 17 00:00:00 2001 From: Kelvin Cao Date: Wed, 29 Nov 2017 10:55:24 -0700 Subject: [PATCH] ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups Allow using Switchtec NTB in setups that have more than two partitions. Note: this does not enable having multi-host communication, it only allows for a single NTB link between two hosts in a network that might have more than two. Use following logic to determine the NT peer partition: 1) If there are 2 partitions, and the target vector is set in the Switchtec configuration, use the partition specified in target vector. 2) If there are 2 partitions and target vector is unset use the only other partition as specified in the NT EP map. 3) If there are more than 2 partitions and target vector is set use the other partition specified in target vector. 4) If there are more than 2 partitions and target vector is unset, this is invalid and report an error. Signed-off-by: Kelvin Cao [logang@deltatee.com: commit message fleshed out] Signed-off-by: Logan Gunthorpe Reviewed-by: Logan Gunthorpe Signed-off-by: Jon Mason --- drivers/ntb/hw/mscc/ntb_hw_switchtec.c | 57 ++++++++++++++++++++++++++++------ include/linux/switchtec.h | 8 +++++ 2 files changed, 56 insertions(+), 9 deletions(-) diff --git a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c index 709f37f..088ae22 100644 --- a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c +++ b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c @@ -777,9 +777,12 @@ static const struct ntb_dev_ops switchtec_ntb_ops = { .peer_spad_addr = switchtec_ntb_peer_spad_addr, }; -static void switchtec_ntb_init_sndev(struct switchtec_ntb *sndev) +static int switchtec_ntb_init_sndev(struct switchtec_ntb *sndev) { + u64 tpart_vec; + int self; u64 part_map; + int bit; sndev->ntb.pdev = sndev->stdev->pdev; sndev->ntb.topo = NTB_TOPO_SWITCH; @@ -788,13 +791,47 @@ static void switchtec_ntb_init_sndev(struct switchtec_ntb *sndev) sndev->self_partition = sndev->stdev->partition; sndev->mmio_ntb = sndev->stdev->mmio_ntb; + + self = sndev->self_partition; + tpart_vec = ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_high); + tpart_vec <<= 32; + tpart_vec |= ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_low); + part_map = ioread64(&sndev->mmio_ntb->ep_map); part_map &= ~(1 << sndev->self_partition); - sndev->peer_partition = ffs(part_map) - 1; - dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d (%llx)\n", - sndev->self_partition, sndev->stdev->partition_count, - part_map); + if (!ffs(tpart_vec)) { + if (sndev->stdev->partition_count != 2) { + dev_err(&sndev->stdev->dev, + "ntb target partition not defined\n"); + return -ENODEV; + } + + bit = ffs(part_map); + if (!bit) { + dev_err(&sndev->stdev->dev, + "peer partition is not NT partition\n"); + return -ENODEV; + } + + sndev->peer_partition = bit - 1; + } else { + if (ffs(tpart_vec) != fls(tpart_vec)) { + dev_err(&sndev->stdev->dev, + "ntb driver only supports 1 pair of 1-1 ntb mapping\n"); + return -ENODEV; + } + + sndev->peer_partition = ffs(tpart_vec) - 1; + if (!(part_map && (1 << sndev->peer_partition))) { + dev_err(&sndev->stdev->dev, + "ntb target partition is not NT partition\n"); + return -ENODEV; + } + } + + dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d\n", + sndev->self_partition, sndev->stdev->partition_count); sndev->mmio_ctrl = (void * __iomem)sndev->mmio_ntb + SWITCHTEC_NTB_REG_CTRL_OFFSET; @@ -804,6 +841,8 @@ static void switchtec_ntb_init_sndev(struct switchtec_ntb *sndev) sndev->mmio_self_ctrl = &sndev->mmio_ctrl[sndev->self_partition]; sndev->mmio_peer_ctrl = &sndev->mmio_ctrl[sndev->peer_partition]; sndev->mmio_self_dbmsg = &sndev->mmio_dbmsg[sndev->self_partition]; + + return 0; } static int map_bars(int *map, struct ntb_ctrl_regs __iomem *ctrl) @@ -1135,15 +1174,15 @@ static int switchtec_ntb_add(struct device *dev, if (stdev->pdev->class != MICROSEMI_NTB_CLASSCODE) return -ENODEV; - if (stdev->partition_count != 2) - dev_warn(dev, "ntb driver only supports 2 partitions\n"); - sndev = kzalloc_node(sizeof(*sndev), GFP_KERNEL, dev_to_node(dev)); if (!sndev) return -ENOMEM; sndev->stdev = stdev; - switchtec_ntb_init_sndev(sndev); + rc = switchtec_ntb_init_sndev(sndev); + if (rc) + goto free_and_exit; + switchtec_ntb_init_mw(sndev); switchtec_ntb_init_db(sndev); switchtec_ntb_init_msgs(sndev); diff --git a/include/linux/switchtec.h b/include/linux/switchtec.h index 09d73d0d..d4a7c18 100644 --- a/include/linux/switchtec.h +++ b/include/linux/switchtec.h @@ -168,6 +168,14 @@ struct ntb_info_regs { u16 reserved1; u64 ep_map; u16 requester_id; + u16 reserved2; + u32 reserved3[4]; + struct nt_partition_info { + u32 xlink_enabled; + u32 target_part_low; + u32 target_part_high; + u32 reserved; + } ntp_info[48]; } __packed; struct part_cfg_regs { -- 2.7.4