diff options
| author | Ben Widawsky <ben.widawsky@intel.com> | 2022-01-23 16:31:13 -0800 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2022-02-08 22:57:31 -0800 |
| commit | 523e594d9cc03db962c741ce02c8a58aab58a123 (patch) | |
| tree | 0c8479f68282ffca41e7e82306bbf2961fc8f4e4 /drivers/cxl/pci.c | |
| parent | 560f78559006a4bab20455ae7eca33d8417c38fc (diff) | |
cxl/pci: Implement wait for media active
CXL 2.0 8.1.3.8.2 states:
Memory_Active: When set, indicates that the CXL Range 1 memory is
fully initialized and available for software use. Must be set within
Range 1. Memory_Active_Timeout of deassertion of reset to CXL device
if CXL.mem HwInit Mode=1
Unfortunately, Memory_Active can take quite a long time depending on
media size (up to 256s per 2.0 spec). Provide a callback for the
eventual establishment of CXL.mem operations via the 'cxl_mem' driver
the 'struct cxl_memdev'. The implementation waits for 60s by default for
now and can be overridden by the mbox_ready_time module parameter.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
[djbw: switch to sleeping wait]
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164298427373.3018233.9309741847039301834.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/cxl/pci.c')
| -rw-r--r-- | drivers/cxl/pci.c | 49 |
1 files changed, 48 insertions, 1 deletions
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 6b3270246545..c01bd44d11c4 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -49,7 +49,7 @@ static unsigned short mbox_ready_timeout = 60; module_param(mbox_ready_timeout, ushort, 0644); MODULE_PARM_DESC(mbox_ready_timeout, - "seconds to wait for mailbox ready status"); + "seconds to wait for mailbox ready / memory active status"); static int cxl_pci_mbox_wait_for_doorbell(struct cxl_dev_state *cxlds) { @@ -418,6 +418,51 @@ static int wait_for_valid(struct cxl_dev_state *cxlds) return -ETIMEDOUT; } +/* + * Wait up to @mbox_ready_timeout for the device to report memory + * active. + */ +static int wait_for_media_ready(struct cxl_dev_state *cxlds) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + bool active = false; + u64 md_status; + int rc, i; + + rc = wait_for_valid(cxlds); + if (rc) + return rc; + + for (i = mbox_ready_timeout; i; i--) { + u32 temp; + int rc; + + rc = pci_read_config_dword( + pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(0), &temp); + if (rc) + return rc; + + active = FIELD_GET(CXL_DVSEC_MEM_ACTIVE, temp); + if (active) + break; + msleep(1000); + } + + if (!active) { + dev_err(&pdev->dev, + "timeout awaiting memory active after %d seconds\n", + mbox_ready_timeout); + return -ETIMEDOUT; + } + + md_status = readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET); + if (!CXLMDEV_READY(md_status)) + return -EIO; + + return 0; +} + static int cxl_dvsec_ranges(struct cxl_dev_state *cxlds) { struct cxl_endpoint_dvsec_info *info = &cxlds->info; @@ -528,6 +573,8 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) dev_warn(&pdev->dev, "Device DVSEC not present, skip CXL.mem init\n"); + cxlds->wait_media_ready = wait_for_media_ready; + rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map); if (rc) return rc; |