On Fri, 10 Jun 2022, ira.weiny@xxxxxxxxx wrote:
+++ b/drivers/cxl/cxlmem.h @@ -191,6 +191,8 @@ struct cxl_endpoint_dvsec_info { * @component_reg_phys: register base of component registers * @info: Cached DVSEC information about the device. * @serial: PCIe Device Serial Number
Missing doc: @doe_use_irq: Use interrupt vectors for DOEs over polling. However introducing such flags is not pretty, and this is only used by devm_cxl_pci_create_doe(). Do we really need it? See below.
+ * @doe_mbs: PCI DOE mailbox array + * @num_mbs: Number of DOE mailboxes * @mbox_send: @dev specific transport for transmitting mailbox commands * * See section 8.2.9.5.2 Capacity Configuration and Label Storage for @@ -224,6 +226,10 @@ struct cxl_dev_state { resource_size_t component_reg_phys; u64 serial; + bool doe_use_irq; + struct pci_doe_mb **doe_mbs; + int num_mbs; + int (*mbox_send)(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd); }; diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 5a0ae46d4989..72c7b535f5df 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -8,6 +8,7 @@ #include <linux/mutex.h> #include <linux/list.h> #include <linux/pci.h> +#include <linux/pci-doe.h> #include <linux/io.h> #include "cxlmem.h" #include "cxlpci.h" @@ -386,6 +387,116 @@ static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type, return rc; } +static void cxl_pci_free_irq_vectors(void *data) +{ + pci_free_irq_vectors(data); +} + +static void cxl_doe_destroy_mb(void *ds) +{ + struct cxl_dev_state *cxlds = ds; + int i; + + for (i = 0; i < cxlds->num_mbs; i++) { + if (cxlds->doe_mbs[i]) + pci_doe_destroy_mb(cxlds->doe_mbs[i]); + } +} + +static void cxl_alloc_irq_vectors(struct cxl_dev_state *cxlds) +{ + struct device *dev = cxlds->dev; + struct pci_dev *pdev = to_pci_dev(dev); + int max_irqs = 0; + int off = 0; + int rc; + + /* Account for all the DOE vectors needed */ + pci_doe_for_each_off(pdev, off) { + int irq = pci_doe_get_irq_num(pdev, off); + + if (irq < 0) + continue; + max_irqs = max(max_irqs, irq + 1); + } + + if (!max_irqs) + return; + + cxlds->doe_use_irq = false;
Is this unnecessary, it should already be 0 per the devm_kzalloc().
+ + /* + * Allocate enough vectors for the DOE's + */ + rc = pci_alloc_irq_vectors(pdev, max_irqs, max_irqs, PCI_IRQ_MSI | + PCI_IRQ_MSIX); + if (rc != max_irqs) { + pci_err(pdev, "Not enough interrupts; use polling\n"); + /* Some got allocated; clean them up */ + if (rc > 0) + cxl_pci_free_irq_vectors(pdev); + return; + } + + rc = devm_add_action_or_reset(dev, cxl_pci_free_irq_vectors, pdev); + if (rc) + return; + + cxlds->doe_use_irq = true; +} + +/** + * devm_cxl_pci_create_doe - Scan and set up DOE mailboxes + * + * @cxlds: The CXL device state + */ +static void devm_cxl_pci_create_doe(struct cxl_dev_state *cxlds) +{ + struct device *dev = cxlds->dev; + struct pci_dev *pdev = to_pci_dev(dev); + u16 off = 0; + int num_mbs = 0; + int rc; + + pci_doe_for_each_off(pdev, off) + num_mbs++; + + if (!num_mbs) { + pci_dbg(pdev, "0 DOE mailbox's found\n"); + return; + } + + cxlds->doe_mbs = devm_kcalloc(dev, num_mbs, sizeof(*cxlds->doe_mbs), + GFP_KERNEL); + if (!cxlds->doe_mbs) + return; + + pci_doe_for_each_off(pdev, off) { + struct pci_doe_mb *doe_mb; + int irq = -1; + + if (cxlds->doe_use_irq) + irq = pci_doe_get_irq_num(pdev, off); + + doe_mb = pci_doe_create_mb(pdev, off, irq); + if (IS_ERR(doe_mb)) { + pci_err(pdev, + "Failed to create MB object for MB @ %x\n", + off); + doe_mb = NULL; + } + + cxlds->doe_mbs[cxlds->num_mbs] = doe_mb; + cxlds->num_mbs++; + } + + rc = devm_add_action_or_reset(dev, cxl_doe_destroy_mb, cxlds); + if (rc) + return; + + pci_info(pdev, "Configured %d DOE mailbox's\n", cxlds->num_mbs); +} + static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct cxl_register_map map; @@ -434,6 +545,9 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) cxlds->component_reg_phys = cxl_regmap_to_base(pdev, &map); + cxl_alloc_irq_vectors(cxlds); + devm_cxl_pci_create_doe(cxlds);
Should cxl_alloc_irq_vectors() just be called directly from devm_cxl_pci_create_doe() instead? Also if devm_cxl_pci_create_doe() fails (say ENOMEM), why do we bother continuing the cxl_pci probing? Thanks, Davidlohr ------ diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h index ce5b00f3ebcb..44098c785a8b 100644 --- a/drivers/cxl/cxlmem.h +++ b/drivers/cxl/cxlmem.h @@ -230,7 +230,6 @@ struct cxl_dev_state { resource_size_t component_reg_phys; u64 serial; - bool doe_use_irq; struct pci_doe_mb **doe_mbs; int num_mbs; diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 72c7b535f5df..47c3741f7768 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -403,7 +403,7 @@ static void cxl_doe_destroy_mb(void *ds) } } -static void cxl_alloc_irq_vectors(struct cxl_dev_state *cxlds) +static int cxl_alloc_irq_vectors(struct cxl_dev_state *cxlds) { struct device *dev = cxlds->dev; struct pci_dev *pdev = to_pci_dev(dev); @@ -421,9 +421,7 @@ static void cxl_alloc_irq_vectors(struct cxl_dev_state *cxlds) } if (!max_irqs) - return; - - cxlds->doe_use_irq = false; + return -ENOMEM; /* * Allocate enough vectors for the DOE's @@ -435,14 +433,10 @@ static void cxl_alloc_irq_vectors(struct cxl_dev_state *cxlds) /* Some got allocated; clean them up */ if (rc > 0) cxl_pci_free_irq_vectors(pdev); - return; + return -ENOMEM; } - rc = devm_add_action_or_reset(dev, cxl_pci_free_irq_vectors, pdev); - if (rc) - return; - - cxlds->doe_use_irq = true; + return devm_add_action_or_reset(dev, cxl_pci_free_irq_vectors, pdev); } /** @@ -457,6 +451,10 @@ static void devm_cxl_pci_create_doe(struct cxl_dev_state *cxlds) u16 off = 0; int num_mbs = 0; int rc; + bool doe_use_irq = false; + + if (cxl_alloc_irq_vectors(cxlds)) + doe_use_irq = true; pci_doe_for_each_off(pdev, off) num_mbs++; @@ -475,7 +473,7 @@ static void devm_cxl_pci_create_doe(struct cxl_dev_state *cxlds) struct pci_doe_mb *doe_mb; int irq = -1; - if (cxlds->doe_use_irq) + if (doe_use_irq) irq = pci_doe_get_irq_num(pdev, off); doe_mb = pci_doe_create_mb(pdev, off, irq); @@ -545,7 +543,6 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) cxlds->component_reg_phys = cxl_regmap_to_base(pdev, &map); - cxl_alloc_irq_vectors(cxlds); devm_cxl_pci_create_doe(cxlds); rc = cxl_pci_setup_mailbox(cxlds);