| Message ID | 20150429202140.GB25904@localhost (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On Wednesday, April 29, 2015 09:21:40 PM Chris Bainbridge wrote: > Regression in commit 7bc5a2bad0b8d9d1ac9f7b8b33150e4ddf197334 > Author: Matthew Garrett <matthew.garrett@nebula.com> > Date: Sat Sep 20 13:19:47 2014 +0200 > > ACPI: Support _OSI("Darwin") correctly > > Supporting _OSI("Darwin") caused the MacBook firmware to expose the SBS, > resulting in intermittent hangs of several minutes on boot, and failure > to detect or report the battery. Fix this by adding a 5us delay to the > start of each SMBUS transaction. This timing is the result of > experimentation - hangs were observed with 3us but never with 5us. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=94651 > Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com> Looks much better, I've queued it up as a fix for 4.1, thanks! > --- > drivers/acpi/sbshc.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/acpi/sbshc.c b/drivers/acpi/sbshc.c > index 26e5b50..bf034f8 100644 > --- a/drivers/acpi/sbshc.c > +++ b/drivers/acpi/sbshc.c > @@ -14,6 +14,7 @@ > #include <linux/delay.h> > #include <linux/module.h> > #include <linux/interrupt.h> > +#include <linux/dmi.h> > #include "sbshc.h" > > #define PREFIX "ACPI: " > @@ -87,6 +88,8 @@ enum acpi_smb_offset { > ACPI_SMB_ALARM_DATA = 0x26, /* 2 bytes alarm data */ > }; > > +static bool macbook; > + > static inline int smb_hc_read(struct acpi_smb_hc *hc, u8 address, u8 *data) > { > return ec_read(hc->offset + address, data); > @@ -132,6 +135,8 @@ static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol, > } > > mutex_lock(&hc->lock); > + if (macbook) > + udelay(5); > if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp)) > goto end; > if (temp) { > @@ -257,12 +262,29 @@ extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, > acpi_handle handle, acpi_ec_query_func func, > void *data); > > +static int macbook_dmi_match(const struct dmi_system_id *d) > +{ > + pr_debug("Detected MacBook, enabling workaround\n"); > + macbook = true; > + return 0; > +} > + > +static struct dmi_system_id acpi_smbus_dmi_table[] = { > + { macbook_dmi_match, "Apple MacBook", { > + DMI_MATCH(DMI_BOARD_VENDOR, "Apple"), > + DMI_MATCH(DMI_PRODUCT_NAME, "MacBook") }, > + }, > + { }, > +}; > + > static int acpi_smbus_hc_add(struct acpi_device *device) > { > int status; > unsigned long long val; > struct acpi_smb_hc *hc; > > + dmi_check_system(acpi_smbus_dmi_table); > + > if (!device) > return -EINVAL; > >
On 30/04/15 04:21, Chris Bainbridge wrote: > > Supporting _OSI("Darwin") caused the MacBook firmware to expose the SBS, > resulting in intermittent hangs of several minutes on boot, and failure > to detect or report the battery. Fix this by adding a 5us delay to the > start of each SMBUS transaction. This timing is the result of > experimentation - hangs were observed with 3us but never with 5us. G'day Chris, Using 4.1-rc3 (whatever git head was from a couple of days ago) I've still been seeing ACPI lockups on my Macbook Pro (11,1). It appears to take a couple of suspend/resume cycles but seems to happen within 24 hours of booting whereas before this patch it was easy to hit. As a test (and I do wonder if it'll lock up after I press send on this E-mail) I upped the delay to 10us and I've now been up for 1 day, 17:23 with the battery still responding to polling. To make it easier to reproduce, I've been running a script that polls the battery every 60 seconds. I figure I'll let it go for another couple of days, but I wanted to put this out there in case anyone else is seeing lockups after a longer period of uptime. The symptoms are the ACPI command just hangs as does 'cat /sys/class/power_supply/BAT0/status'. From there I can't suspend as the tasks can't be frozen and I just end up hard booting the machine. I've removed Len & Rafael from the cc. Regards, Brad -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/sbshc.c b/drivers/acpi/sbshc.c index 26e5b50..bf034f8 100644 --- a/drivers/acpi/sbshc.c +++ b/drivers/acpi/sbshc.c @@ -14,6 +14,7 @@ #include <linux/delay.h> #include <linux/module.h> #include <linux/interrupt.h> +#include <linux/dmi.h> #include "sbshc.h" #define PREFIX "ACPI: " @@ -87,6 +88,8 @@ enum acpi_smb_offset { ACPI_SMB_ALARM_DATA = 0x26, /* 2 bytes alarm data */ }; +static bool macbook; + static inline int smb_hc_read(struct acpi_smb_hc *hc, u8 address, u8 *data) { return ec_read(hc->offset + address, data); @@ -132,6 +135,8 @@ static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol, } mutex_lock(&hc->lock); + if (macbook) + udelay(5); if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp)) goto end; if (temp) { @@ -257,12 +262,29 @@ extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, acpi_handle handle, acpi_ec_query_func func, void *data); +static int macbook_dmi_match(const struct dmi_system_id *d) +{ + pr_debug("Detected MacBook, enabling workaround\n"); + macbook = true; + return 0; +} + +static struct dmi_system_id acpi_smbus_dmi_table[] = { + { macbook_dmi_match, "Apple MacBook", { + DMI_MATCH(DMI_BOARD_VENDOR, "Apple"), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBook") }, + }, + { }, +}; + static int acpi_smbus_hc_add(struct acpi_device *device) { int status; unsigned long long val; struct acpi_smb_hc *hc; + dmi_check_system(acpi_smbus_dmi_table); + if (!device) return -EINVAL;
Regression in commit 7bc5a2bad0b8d9d1ac9f7b8b33150e4ddf197334 Author: Matthew Garrett <matthew.garrett@nebula.com> Date: Sat Sep 20 13:19:47 2014 +0200 ACPI: Support _OSI("Darwin") correctly Supporting _OSI("Darwin") caused the MacBook firmware to expose the SBS, resulting in intermittent hangs of several minutes on boot, and failure to detect or report the battery. Fix this by adding a 5us delay to the start of each SMBUS transaction. This timing is the result of experimentation - hangs were observed with 3us but never with 5us. Link: https://bugzilla.kernel.org/show_bug.cgi?id=94651 Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com> --- drivers/acpi/sbshc.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)