From: Ben Widawsky <[email protected]> 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 <[email protected]> [djbw: switch to sleeping wait] Signed-off-by: Dan Williams <[email protected]> --- drivers/cxl/cxlmem.h | 2 ++ drivers/cxl/pci.c | 49 +++++++++++++++++++++++++++++++++++++++++- tools/testing/cxl/test/mem.c | 8 +++++++ 3 files changed, 58 insertions(+), 1 deletion(-) diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h index 00f55f4066b9..e70838e5dc17 100644 --- a/drivers/cxl/cxlmem.h +++ b/drivers/cxl/cxlmem.h @@ -132,6 +132,7 @@ struct cxl_endpoint_dvsec_info { * @component_reg_phys: register base of component registers * @info: Cached DVSEC information about the device. * @mbox_send: @dev specific transport for transmitting mailbox commands + * @wait_media_ready: @dev specific method to await media ready * * See section 8.2.9.5.2 Capacity Configuration and Label Storage for * details on capacity parameters. @@ -165,6 +166,7 @@ struct cxl_dev_state { struct cxl_endpoint_dvsec_info info; int (*mbox_send)(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd); + int (*wait_media_ready)(struct cxl_dev_state *cxlds); }; enum cxl_opcode { diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 5c43886dc2af..513cb0e2a70a 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, 0600); 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) { @@ -417,6 +417,51 @@ 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; @@ -520,6 +565,8 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) return -ENXIO; } + cxlds->wait_media_ready = wait_for_media_ready; + rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map); if (rc) return rc; diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c index 8c2086c4caef..3af3f94de0c3 100644 --- a/tools/testing/cxl/test/mem.c +++ b/tools/testing/cxl/test/mem.c @@ -4,6 +4,7 @@ #include <linux/platform_device.h> #include <linux/mod_devicetable.h> #include <linux/module.h> +#include <linux/delay.h> #include <linux/sizes.h> #include <linux/bits.h> #include <cxlmem.h> @@ -236,6 +237,12 @@ static int cxl_mock_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd * return rc; } +static int cxl_mock_wait_media_ready(struct cxl_dev_state *cxlds) +{ + msleep(100); + return 0; +} + static void label_area_release(void *lsa) { vfree(lsa); @@ -262,6 +269,7 @@ static int cxl_mock_mem_probe(struct platform_device *pdev) return PTR_ERR(cxlds); cxlds->mbox_send = cxl_mock_mbox_send; + cxlds->wait_media_ready = cxl_mock_wait_media_ready; cxlds->payload_size = SZ_4K; rc = cxl_enumerate_cmds(cxlds);
