From 3af4b40b0f2f194d32e90cc5d25ebb3daa96cd1f Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Mon, 28 Nov 2022 12:36:47 -0800 Subject: ice: implement direct read for NVM and Shadow RAM regions Implement the .read handler for the NVM and Shadow RAM regions. This enables user space to read a small chunk of the flash without needing the overhead of creating a full snapshot. Update the documentation for ice to detail which regions have direct read support. Signed-off-by: Jacob Keller Acked-by: Jakub Kicinski Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/intel/ice/ice_devlink.c | 69 ++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) (limited to 'drivers/net/ethernet/intel') diff --git a/drivers/net/ethernet/intel/ice/ice_devlink.c b/drivers/net/ethernet/intel/ice/ice_devlink.c index 9d3500291d2e..946d64e577c9 100644 --- a/drivers/net/ethernet/intel/ice/ice_devlink.c +++ b/drivers/net/ethernet/intel/ice/ice_devlink.c @@ -1687,6 +1687,73 @@ static int ice_devlink_nvm_snapshot(struct devlink *devlink, return 0; } +/** + * ice_devlink_nvm_read - Read a portion of NVM flash contents + * @devlink: the devlink instance + * @ops: the devlink region to snapshot + * @extack: extended ACK response structure + * @offset: the offset to start at + * @size: the amount to read + * @data: the data buffer to read into + * + * This function is called in response to DEVLINK_CMD_REGION_READ to directly + * read a section of the NVM contents. + * + * It reads from either the nvm-flash or shadow-ram region contents. + * + * @returns zero on success, and updates the data pointer. Returns a non-zero + * error code on failure. + */ +static int ice_devlink_nvm_read(struct devlink *devlink, + const struct devlink_region_ops *ops, + struct netlink_ext_ack *extack, + u64 offset, u32 size, u8 *data) +{ + struct ice_pf *pf = devlink_priv(devlink); + struct device *dev = ice_pf_to_dev(pf); + struct ice_hw *hw = &pf->hw; + bool read_shadow_ram; + u64 nvm_size; + int status; + + if (ops == &ice_nvm_region_ops) { + read_shadow_ram = false; + nvm_size = hw->flash.flash_size; + } else if (ops == &ice_sram_region_ops) { + read_shadow_ram = true; + nvm_size = hw->flash.sr_words * 2u; + } else { + NL_SET_ERR_MSG_MOD(extack, "Unexpected region in snapshot function"); + return -EOPNOTSUPP; + } + + if (offset + size >= nvm_size) { + NL_SET_ERR_MSG_MOD(extack, "Cannot read beyond the region size"); + return -ERANGE; + } + + status = ice_acquire_nvm(hw, ICE_RES_READ); + if (status) { + dev_dbg(dev, "ice_acquire_nvm failed, err %d aq_err %d\n", + status, hw->adminq.sq_last_status); + NL_SET_ERR_MSG_MOD(extack, "Failed to acquire NVM semaphore"); + return -EIO; + } + + status = ice_read_flat_nvm(hw, (u32)offset, &size, data, + read_shadow_ram); + if (status) { + dev_dbg(dev, "ice_read_flat_nvm failed after reading %u bytes, err %d aq_err %d\n", + size, status, hw->adminq.sq_last_status); + NL_SET_ERR_MSG_MOD(extack, "Failed to read NVM contents"); + ice_release_nvm(hw); + return -EIO; + } + ice_release_nvm(hw); + + return 0; +} + /** * ice_devlink_devcaps_snapshot - Capture snapshot of device capabilities * @devlink: the devlink instance @@ -1735,12 +1802,14 @@ static const struct devlink_region_ops ice_nvm_region_ops = { .name = "nvm-flash", .destructor = vfree, .snapshot = ice_devlink_nvm_snapshot, + .read = ice_devlink_nvm_read, }; static const struct devlink_region_ops ice_sram_region_ops = { .name = "shadow-ram", .destructor = vfree, .snapshot = ice_devlink_nvm_snapshot, + .read = ice_devlink_nvm_read, }; static const struct devlink_region_ops ice_devcaps_region_ops = { -- cgit v1.2.3