From 1e7d6a45f6b10bc48a1453bca3d829e210546571 Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Fri, 3 Apr 2015 12:13:48 -0500 Subject: [PATCH] ipmi: Handle BMCs that don't allow clearing the rcv irq bit Some BMCs don't let you clear the receive irq bit in the global enables. This is kind of silly, but they give an error if you try to clear it. Compensate for this by detecting the situation and working around it. Signed-off-by: Corey Minyard Tested-by: Thomas D Reviewed-by: Thomas D --- drivers/char/ipmi/ipmi_si_intf.c | 109 +++++++++++++++++++++++++++++-- 1 file changed, 102 insertions(+), 7 deletions(-) diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c index f6646ed3047e..518585c1ce94 100644 --- a/drivers/char/ipmi/ipmi_si_intf.c +++ b/drivers/char/ipmi/ipmi_si_intf.c @@ -262,6 +262,11 @@ struct smi_info { */ bool supports_event_msg_buff; + /* + * Can we clear the global enables receive irq bit? + */ + bool cannot_clear_recv_irq_bit; + /* * Did we get an attention that we did not handle? */ @@ -461,6 +466,9 @@ static void smi_mod_timer(struct smi_info *smi_info, unsigned long new_val) * allocate messages, we just leave them in the BMC and run the system * polled until we can allocate some memory. Once we have some * memory, we will re-enable the interrupt. + * + * Note that we cannot just use disable_irq(), since the interrupt may + * be shared. */ static inline bool disable_si_irq(struct smi_info *smi_info) { @@ -549,20 +557,15 @@ static u8 current_global_enables(struct smi_info *smi_info, u8 base, if (smi_info->supports_event_msg_buff) enables |= IPMI_BMC_EVT_MSG_BUFF; - else - enables &= ~IPMI_BMC_EVT_MSG_BUFF; - if (smi_info->irq && !smi_info->interrupt_disabled) + if ((smi_info->irq && !smi_info->interrupt_disabled) || + smi_info->cannot_clear_recv_irq_bit) enables |= IPMI_BMC_RCV_MSG_INTR; - else - enables &= ~IPMI_BMC_RCV_MSG_INTR; if (smi_info->supports_event_msg_buff && smi_info->irq && !smi_info->interrupt_disabled) enables |= IPMI_BMC_EVT_MSG_INTR; - else - enables &= ~IPMI_BMC_EVT_MSG_INTR; *irq_on = enables & (IPMI_BMC_EVT_MSG_INTR | IPMI_BMC_RCV_MSG_INTR); @@ -2900,6 +2903,96 @@ static int try_get_dev_id(struct smi_info *smi_info) return rv; } +/* + * Some BMCs do not support clearing the receive irq bit in the global + * enables (even if they don't support interrupts on the BMC). Check + * for this and handle it properly. + */ +static void check_clr_rcv_irq(struct smi_info *smi_info) +{ + unsigned char msg[3]; + unsigned char *resp; + unsigned long resp_len; + int rv; + + resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL); + if (!resp) { + printk(KERN_WARNING PFX "Out of memory allocating response for" + " global enables command, cannot check recv irq bit" + " handling.\n"); + return; + } + + msg[0] = IPMI_NETFN_APP_REQUEST << 2; + msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD; + smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2); + + rv = wait_for_msg_done(smi_info); + if (rv) { + printk(KERN_WARNING PFX "Error getting response from get" + " global enables command, cannot check recv irq bit" + " handling.\n"); + goto out; + } + + resp_len = smi_info->handlers->get_result(smi_info->si_sm, + resp, IPMI_MAX_MSG_LENGTH); + + if (resp_len < 4 || + resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 || + resp[1] != IPMI_GET_BMC_GLOBAL_ENABLES_CMD || + resp[2] != 0) { + printk(KERN_WARNING PFX "Invalid return from get global" + " enables command, cannot check recv irq bit" + " handling.\n"); + rv = -EINVAL; + goto out; + } + + if ((resp[3] & IPMI_BMC_RCV_MSG_INTR) == 0) + /* Already clear, should work ok. */ + goto out; + + msg[0] = IPMI_NETFN_APP_REQUEST << 2; + msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD; + msg[2] = resp[3] & ~IPMI_BMC_RCV_MSG_INTR; + smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3); + + rv = wait_for_msg_done(smi_info); + if (rv) { + printk(KERN_WARNING PFX "Error getting response from set" + " global enables command, cannot check recv irq bit" + " handling.\n"); + goto out; + } + + resp_len = smi_info->handlers->get_result(smi_info->si_sm, + resp, IPMI_MAX_MSG_LENGTH); + + if (resp_len < 3 || + resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 || + resp[1] != IPMI_SET_BMC_GLOBAL_ENABLES_CMD) { + printk(KERN_WARNING PFX "Invalid return from get global" + " enables command, cannot check recv irq bit" + " handling.\n"); + rv = -EINVAL; + goto out; + } + + if (resp[2] != 0) { + /* + * An error when setting the event buffer bit means + * clearing the bit is not supported. + */ + printk(KERN_WARNING PFX "The BMC does not support clearing" + " the recv irq bit, compensating, but the BMC needs to" + " be fixed.\n"); + smi_info->cannot_clear_recv_irq_bit = true; + } + out: + kfree(resp); +} + static int try_enable_event_buffer(struct smi_info *smi_info) { unsigned char msg[3]; @@ -3395,6 +3488,8 @@ static int try_smi_init(struct smi_info *new_smi) goto out_err; } + check_clr_rcv_irq(new_smi); + setup_oem_data_handler(new_smi); setup_xaction_handlers(new_smi); -- 2.20.1