From b27759f880018b0cd43543dc94c921341b64b5ec Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 18 Jun 2010 17:04:22 +0200 Subject: PCI/PM: Do not use native PCIe PME by default MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit c7f486567c1d0acd2e4166c47069835b9f75e77b (PCI PM: PCIe PME root port service driver) causes the native PCIe PME signaling to be used by default, if the BIOS allows the kernel to control the standard configuration registers of PCIe root ports. However, the native PCIe PME is coupled to the native PCIe hotplug and calling pcie_pme_acpi_setup() makes some BIOSes expect that the native PCIe hotplug will be used as well. That, in turn, causes problems to appear on systems where the PCIe hotplug driver is not loaded. The usual symptom, as reported by Jaroslav Kameník and others, is that the ACPI GPE associated with PCIe hotplug keeps firing continuously causing kacpid to take substantial percentage of CPU time. To work around this issue, change the default so that the native PCIe PME signaling is only used if directly requested with the help of the pcie_pme= command line switch. Fixes https://bugzilla.kernel.org/show_bug.cgi?id=15924 , which is a listed regression from 2.6.33. Signed-off-by: Rafael J. Wysocki Reported-by: Jaroslav Kameník Tested-by: Antoni Grzymala Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 1808f1157f30..82d6aeb5228f 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2048,7 +2048,9 @@ and is between 256 and 4096 characters. It is defined in the file WARNING: Forcing ASPM on may cause system lockups. pcie_pme= [PCIE,PM] Native PCIe PME signaling options: - off Do not use native PCIe PME signaling. + Format: {auto|force}[,nomsi] + auto Use native PCIe PME signaling if the BIOS allows the + kernel to control PCIe config registers of root ports. force Use native PCIe PME signaling even if the BIOS refuses to allow the kernel to control the relevant PCIe config registers. -- cgit From 476099a1b3950285013dd8df0869df6fceaf6579 Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Thu, 24 Jun 2010 09:43:25 -0700 Subject: watchdog: docs: add an entry for imx2_wdt Add an entry for imx2_wdt in watchdog-parameters.txt Signed-off-by: Fabio Estevam Acked-by: Wolfram Sang Signed-off-by: Wim Van Sebroeck --- Documentation/watchdog/watchdog-parameters.txt | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'Documentation') diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt index 41c95cc1dc1f..17ddd822b456 100644 --- a/Documentation/watchdog/watchdog-parameters.txt +++ b/Documentation/watchdog/watchdog-parameters.txt @@ -125,6 +125,11 @@ ibmasr: nowayout: Watchdog cannot be stopped once started (default=kernel config parameter) ------------------------------------------------- +imx2_wdt: +timeout: Watchdog timeout in seconds (default 60 s) +nowayout: Watchdog cannot be stopped once started + (default=kernel config parameter) +------------------------------------------------- indydog: nowayout: Watchdog cannot be stopped once started (default=kernel config parameter) -- cgit From bd1fc7c59669fba897d23d72289341ac9d51ca4e Mon Sep 17 00:00:00 2001 From: Andy Walls Date: Thu, 17 Jun 2010 22:24:09 -0300 Subject: V4L/DVB: Documentation: Add the Philips FQ1236 MK5 to video4linux/CARDLIST.tuner Signed-off-by: Andy Walls Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.tuner | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.tuner b/Documentation/video4linux/CARDLIST.tuner index 9b2e0dd6017e..e67c1db96854 100644 --- a/Documentation/video4linux/CARDLIST.tuner +++ b/Documentation/video4linux/CARDLIST.tuner @@ -82,3 +82,4 @@ tuner=81 - Partsnic (Daewoo) PTI-5NF05 tuner=82 - Philips CU1216L tuner=83 - NXP TDA18271 tuner=84 - Sony BTF-Pxn01Z +tuner=85 - Philips FQ1236 MK5 -- cgit From 95f72d1ed41a66f1c1c29c24d479de81a0bea36f Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Mon, 12 Jul 2010 14:36:09 +1000 Subject: lmb: rename to memblock via following scripts FILES=$(find * -type f | grep -vE 'oprofile|[^K]config') sed -i \ -e 's/lmb/memblock/g' \ -e 's/LMB/MEMBLOCK/g' \ $FILES for N in $(find . -name lmb.[ch]); do M=$(echo $N | sed 's/lmb/memblock/g') mv $N $M done and remove some wrong change like lmbench and dlmb etc. also move memblock.c from lib/ to mm/ Suggested-by: Ingo Molnar Acked-by: "H. Peter Anvin" Acked-by: Benjamin Herrenschmidt Acked-by: Linus Torvalds Signed-off-by: Yinghai Lu Signed-off-by: Benjamin Herrenschmidt --- Documentation/kernel-parameters.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 82d6aeb5228f..4ddb58df081e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1265,7 +1265,7 @@ and is between 256 and 4096 characters. It is defined in the file If there are multiple matching configurations changing the same attribute, the last one is used. - lmb=debug [KNL] Enable lmb debug messages. + memblock=debug [KNL] Enable memblock debug messages. load_ramdisk= [RAM] List of ramdisks to load from floppy See Documentation/blockdev/ramdisk.txt. -- cgit From 9fe41e4197f351bc78547ab2d8808e1aca30d87c Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Mon, 19 Jul 2010 22:20:27 +0000 Subject: documentation: fix almost duplicate filenames (IO/io-mapping.txt) Having both IO-mapping.txt and io-mapping.txt in Documentation/ was confusing and/or bothersome to some people, so rename IO-mapping.txt to bus-virt-phys-mapping.txt. Also update Documentation/00-INDEX for both of these files. Signed-off-by: Randy Dunlap Cc: Kees Bakker Cc: Keith Packard --- Documentation/00-INDEX | 6 +- Documentation/IO-mapping.txt | 208 -------------------------------- Documentation/bus-virt-phys-mapping.txt | 208 ++++++++++++++++++++++++++++++++ 3 files changed, 212 insertions(+), 210 deletions(-) delete mode 100644 Documentation/IO-mapping.txt create mode 100644 Documentation/bus-virt-phys-mapping.txt (limited to 'Documentation') diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX index dd10b51b4e65..5405f7aecefc 100644 --- a/Documentation/00-INDEX +++ b/Documentation/00-INDEX @@ -32,8 +32,6 @@ DocBook/ - directory with DocBook templates etc. for kernel documentation. HOWTO - the process and procedures of how to do Linux kernel development. -IO-mapping.txt - - how to access I/O mapped memory from within device drivers. IPMI.txt - info on Linux Intelligent Platform Management Interface (IPMI) Driver. IRQ-affinity.txt @@ -84,6 +82,8 @@ blockdev/ - info on block devices & drivers btmrvl.txt - info on Marvell Bluetooth driver usage. +bus-virt-phys-mapping.txt + - how to access I/O mapped memory from within device drivers. cachetlb.txt - describes the cache/TLB flushing interfaces Linux uses. cdrom/ @@ -168,6 +168,8 @@ initrd.txt - how to use the RAM disk as an initial/temporary root filesystem. input/ - info on Linux input device support. +io-mapping.txt + - description of io_mapping functions in linux/io-mapping.h io_ordering.txt - info on ordering I/O writes to memory-mapped addresses. ioctl/ diff --git a/Documentation/IO-mapping.txt b/Documentation/IO-mapping.txt deleted file mode 100644 index 1b5aa10df845..000000000000 --- a/Documentation/IO-mapping.txt +++ /dev/null @@ -1,208 +0,0 @@ -[ NOTE: The virt_to_bus() and bus_to_virt() functions have been - superseded by the functionality provided by the PCI DMA interface - (see Documentation/PCI/PCI-DMA-mapping.txt). They continue - to be documented below for historical purposes, but new code - must not use them. --davidm 00/12/12 ] - -[ This is a mail message in response to a query on IO mapping, thus the - strange format for a "document" ] - -The AHA-1542 is a bus-master device, and your patch makes the driver give the -controller the physical address of the buffers, which is correct on x86 -(because all bus master devices see the physical memory mappings directly). - -However, on many setups, there are actually _three_ different ways of looking -at memory addresses, and in this case we actually want the third, the -so-called "bus address". - -Essentially, the three ways of addressing memory are (this is "real memory", -that is, normal RAM--see later about other details): - - - CPU untranslated. This is the "physical" address. Physical address - 0 is what the CPU sees when it drives zeroes on the memory bus. - - - CPU translated address. This is the "virtual" address, and is - completely internal to the CPU itself with the CPU doing the appropriate - translations into "CPU untranslated". - - - bus address. This is the address of memory as seen by OTHER devices, - not the CPU. Now, in theory there could be many different bus - addresses, with each device seeing memory in some device-specific way, but - happily most hardware designers aren't actually actively trying to make - things any more complex than necessary, so you can assume that all - external hardware sees the memory the same way. - -Now, on normal PCs the bus address is exactly the same as the physical -address, and things are very simple indeed. However, they are that simple -because the memory and the devices share the same address space, and that is -not generally necessarily true on other PCI/ISA setups. - -Now, just as an example, on the PReP (PowerPC Reference Platform), the -CPU sees a memory map something like this (this is from memory): - - 0-2 GB "real memory" - 2 GB-3 GB "system IO" (inb/out and similar accesses on x86) - 3 GB-4 GB "IO memory" (shared memory over the IO bus) - -Now, that looks simple enough. However, when you look at the same thing from -the viewpoint of the devices, you have the reverse, and the physical memory -address 0 actually shows up as address 2 GB for any IO master. - -So when the CPU wants any bus master to write to physical memory 0, it -has to give the master address 0x80000000 as the memory address. - -So, for example, depending on how the kernel is actually mapped on the -PPC, you can end up with a setup like this: - - physical address: 0 - virtual address: 0xC0000000 - bus address: 0x80000000 - -where all the addresses actually point to the same thing. It's just seen -through different translations.. - -Similarly, on the Alpha, the normal translation is - - physical address: 0 - virtual address: 0xfffffc0000000000 - bus address: 0x40000000 - -(but there are also Alphas where the physical address and the bus address -are the same). - -Anyway, the way to look up all these translations, you do - - #include - - phys_addr = virt_to_phys(virt_addr); - virt_addr = phys_to_virt(phys_addr); - bus_addr = virt_to_bus(virt_addr); - virt_addr = bus_to_virt(bus_addr); - -Now, when do you need these? - -You want the _virtual_ address when you are actually going to access that -pointer from the kernel. So you can have something like this: - - /* - * this is the hardware "mailbox" we use to communicate with - * the controller. The controller sees this directly. - */ - struct mailbox { - __u32 status; - __u32 bufstart; - __u32 buflen; - .. - } mbox; - - unsigned char * retbuffer; - - /* get the address from the controller */ - retbuffer = bus_to_virt(mbox.bufstart); - switch (retbuffer[0]) { - case STATUS_OK: - ... - -on the other hand, you want the bus address when you have a buffer that -you want to give to the controller: - - /* ask the controller to read the sense status into "sense_buffer" */ - mbox.bufstart = virt_to_bus(&sense_buffer); - mbox.buflen = sizeof(sense_buffer); - mbox.status = 0; - notify_controller(&mbox); - -And you generally _never_ want to use the physical address, because you can't -use that from the CPU (the CPU only uses translated virtual addresses), and -you can't use it from the bus master. - -So why do we care about the physical address at all? We do need the physical -address in some cases, it's just not very often in normal code. The physical -address is needed if you use memory mappings, for example, because the -"remap_pfn_range()" mm function wants the physical address of the memory to -be remapped as measured in units of pages, a.k.a. the pfn (the memory -management layer doesn't know about devices outside the CPU, so it -shouldn't need to know about "bus addresses" etc). - -NOTE NOTE NOTE! The above is only one part of the whole equation. The above -only talks about "real memory", that is, CPU memory (RAM). - -There is a completely different type of memory too, and that's the "shared -memory" on the PCI or ISA bus. That's generally not RAM (although in the case -of a video graphics card it can be normal DRAM that is just used for a frame -buffer), but can be things like a packet buffer in a network card etc. - -This memory is called "PCI memory" or "shared memory" or "IO memory" or -whatever, and there is only one way to access it: the readb/writeb and -related functions. You should never take the address of such memory, because -there is really nothing you can do with such an address: it's not -conceptually in the same memory space as "real memory" at all, so you cannot -just dereference a pointer. (Sadly, on x86 it _is_ in the same memory space, -so on x86 it actually works to just deference a pointer, but it's not -portable). - -For such memory, you can do things like - - - reading: - /* - * read first 32 bits from ISA memory at 0xC0000, aka - * C000:0000 in DOS terms - */ - unsigned int signature = isa_readl(0xC0000); - - - remapping and writing: - /* - * remap framebuffer PCI memory area at 0xFC000000, - * size 1MB, so that we can access it: We can directly - * access only the 640k-1MB area, so anything else - * has to be remapped. - */ - void __iomem *baseptr = ioremap(0xFC000000, 1024*1024); - - /* write a 'A' to the offset 10 of the area */ - writeb('A',baseptr+10); - - /* unmap when we unload the driver */ - iounmap(baseptr); - - - copying and clearing: - /* get the 6-byte Ethernet address at ISA address E000:0040 */ - memcpy_fromio(kernel_buffer, 0xE0040, 6); - /* write a packet to the driver */ - memcpy_toio(0xE1000, skb->data, skb->len); - /* clear the frame buffer */ - memset_io(0xA0000, 0, 0x10000); - -OK, that just about covers the basics of accessing IO portably. Questions? -Comments? You may think that all the above is overly complex, but one day you -might find yourself with a 500 MHz Alpha in front of you, and then you'll be -happy that your driver works ;) - -Note that kernel versions 2.0.x (and earlier) mistakenly called the -ioremap() function "vremap()". ioremap() is the proper name, but I -didn't think straight when I wrote it originally. People who have to -support both can do something like: - - /* support old naming silliness */ - #if LINUX_VERSION_CODE < 0x020100 - #define ioremap vremap - #define iounmap vfree - #endif - -at the top of their source files, and then they can use the right names -even on 2.0.x systems. - -And the above sounds worse than it really is. Most real drivers really -don't do all that complex things (or rather: the complexity is not so -much in the actual IO accesses as in error handling and timeouts etc). -It's generally not hard to fix drivers, and in many cases the code -actually looks better afterwards: - - unsigned long signature = *(unsigned int *) 0xC0000; - vs - unsigned long signature = readl(0xC0000); - -I think the second version actually is more readable, no? - - Linus - diff --git a/Documentation/bus-virt-phys-mapping.txt b/Documentation/bus-virt-phys-mapping.txt new file mode 100644 index 000000000000..1b5aa10df845 --- /dev/null +++ b/Documentation/bus-virt-phys-mapping.txt @@ -0,0 +1,208 @@ +[ NOTE: The virt_to_bus() and bus_to_virt() functions have been + superseded by the functionality provided by the PCI DMA interface + (see Documentation/PCI/PCI-DMA-mapping.txt). They continue + to be documented below for historical purposes, but new code + must not use them. --davidm 00/12/12 ] + +[ This is a mail message in response to a query on IO mapping, thus the + strange format for a "document" ] + +The AHA-1542 is a bus-master device, and your patch makes the driver give the +controller the physical address of the buffers, which is correct on x86 +(because all bus master devices see the physical memory mappings directly). + +However, on many setups, there are actually _three_ different ways of looking +at memory addresses, and in this case we actually want the third, the +so-called "bus address". + +Essentially, the three ways of addressing memory are (this is "real memory", +that is, normal RAM--see later about other details): + + - CPU untranslated. This is the "physical" address. Physical address + 0 is what the CPU sees when it drives zeroes on the memory bus. + + - CPU translated address. This is the "virtual" address, and is + completely internal to the CPU itself with the CPU doing the appropriate + translations into "CPU untranslated". + + - bus address. This is the address of memory as seen by OTHER devices, + not the CPU. Now, in theory there could be many different bus + addresses, with each device seeing memory in some device-specific way, but + happily most hardware designers aren't actually actively trying to make + things any more complex than necessary, so you can assume that all + external hardware sees the memory the same way. + +Now, on normal PCs the bus address is exactly the same as the physical +address, and things are very simple indeed. However, they are that simple +because the memory and the devices share the same address space, and that is +not generally necessarily true on other PCI/ISA setups. + +Now, just as an example, on the PReP (PowerPC Reference Platform), the +CPU sees a memory map something like this (this is from memory): + + 0-2 GB "real memory" + 2 GB-3 GB "system IO" (inb/out and similar accesses on x86) + 3 GB-4 GB "IO memory" (shared memory over the IO bus) + +Now, that looks simple enough. However, when you look at the same thing from +the viewpoint of the devices, you have the reverse, and the physical memory +address 0 actually shows up as address 2 GB for any IO master. + +So when the CPU wants any bus master to write to physical memory 0, it +has to give the master address 0x80000000 as the memory address. + +So, for example, depending on how the kernel is actually mapped on the +PPC, you can end up with a setup like this: + + physical address: 0 + virtual address: 0xC0000000 + bus address: 0x80000000 + +where all the addresses actually point to the same thing. It's just seen +through different translations.. + +Similarly, on the Alpha, the normal translation is + + physical address: 0 + virtual address: 0xfffffc0000000000 + bus address: 0x40000000 + +(but there are also Alphas where the physical address and the bus address +are the same). + +Anyway, the way to look up all these translations, you do + + #include + + phys_addr = virt_to_phys(virt_addr); + virt_addr = phys_to_virt(phys_addr); + bus_addr = virt_to_bus(virt_addr); + virt_addr = bus_to_virt(bus_addr); + +Now, when do you need these? + +You want the _virtual_ address when you are actually going to access that +pointer from the kernel. So you can have something like this: + + /* + * this is the hardware "mailbox" we use to communicate with + * the controller. The controller sees this directly. + */ + struct mailbox { + __u32 status; + __u32 bufstart; + __u32 buflen; + .. + } mbox; + + unsigned char * retbuffer; + + /* get the address from the controller */ + retbuffer = bus_to_virt(mbox.bufstart); + switch (retbuffer[0]) { + case STATUS_OK: + ... + +on the other hand, you want the bus address when you have a buffer that +you want to give to the controller: + + /* ask the controller to read the sense status into "sense_buffer" */ + mbox.bufstart = virt_to_bus(&sense_buffer); + mbox.buflen = sizeof(sense_buffer); + mbox.status = 0; + notify_controller(&mbox); + +And you generally _never_ want to use the physical address, because you can't +use that from the CPU (the CPU only uses translated virtual addresses), and +you can't use it from the bus master. + +So why do we care about the physical address at all? We do need the physical +address in some cases, it's just not very often in normal code. The physical +address is needed if you use memory mappings, for example, because the +"remap_pfn_range()" mm function wants the physical address of the memory to +be remapped as measured in units of pages, a.k.a. the pfn (the memory +management layer doesn't know about devices outside the CPU, so it +shouldn't need to know about "bus addresses" etc). + +NOTE NOTE NOTE! The above is only one part of the whole equation. The above +only talks about "real memory", that is, CPU memory (RAM). + +There is a completely different type of memory too, and that's the "shared +memory" on the PCI or ISA bus. That's generally not RAM (although in the case +of a video graphics card it can be normal DRAM that is just used for a frame +buffer), but can be things like a packet buffer in a network card etc. + +This memory is called "PCI memory" or "shared memory" or "IO memory" or +whatever, and there is only one way to access it: the readb/writeb and +related functions. You should never take the address of such memory, because +there is really nothing you can do with such an address: it's not +conceptually in the same memory space as "real memory" at all, so you cannot +just dereference a pointer. (Sadly, on x86 it _is_ in the same memory space, +so on x86 it actually works to just deference a pointer, but it's not +portable). + +For such memory, you can do things like + + - reading: + /* + * read first 32 bits from ISA memory at 0xC0000, aka + * C000:0000 in DOS terms + */ + unsigned int signature = isa_readl(0xC0000); + + - remapping and writing: + /* + * remap framebuffer PCI memory area at 0xFC000000, + * size 1MB, so that we can access it: We can directly + * access only the 640k-1MB area, so anything else + * has to be remapped. + */ + void __iomem *baseptr = ioremap(0xFC000000, 1024*1024); + + /* write a 'A' to the offset 10 of the area */ + writeb('A',baseptr+10); + + /* unmap when we unload the driver */ + iounmap(baseptr); + + - copying and clearing: + /* get the 6-byte Ethernet address at ISA address E000:0040 */ + memcpy_fromio(kernel_buffer, 0xE0040, 6); + /* write a packet to the driver */ + memcpy_toio(0xE1000, skb->data, skb->len); + /* clear the frame buffer */ + memset_io(0xA0000, 0, 0x10000); + +OK, that just about covers the basics of accessing IO portably. Questions? +Comments? You may think that all the above is overly complex, but one day you +might find yourself with a 500 MHz Alpha in front of you, and then you'll be +happy that your driver works ;) + +Note that kernel versions 2.0.x (and earlier) mistakenly called the +ioremap() function "vremap()". ioremap() is the proper name, but I +didn't think straight when I wrote it originally. People who have to +support both can do something like: + + /* support old naming silliness */ + #if LINUX_VERSION_CODE < 0x020100 + #define ioremap vremap + #define iounmap vfree + #endif + +at the top of their source files, and then they can use the right names +even on 2.0.x systems. + +And the above sounds worse than it really is. Most real drivers really +don't do all that complex things (or rather: the complexity is not so +much in the actual IO accesses as in error handling and timeouts etc). +It's generally not hard to fix drivers, and in many cases the code +actually looks better afterwards: + + unsigned long signature = *(unsigned int *) 0xC0000; + vs + unsigned long signature = readl(0xC0000); + +I think the second version actually is more readable, no? + + Linus + -- cgit From 72ad5d77fb981963edae15eee8196c80238f5ed0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 23 Jul 2010 22:59:09 +0200 Subject: ACPI / Sleep: Allow the NVS saving to be skipped during suspend to RAM Commit 2a6b69765ad794389f2fc3e14a0afa1a995221c2 (ACPI: Store NVS state even when entering suspend to RAM) caused the ACPI suspend code save the NVS area during suspend and restore it during resume unconditionally, although it is known that some systems need to use acpi_sleep=s4_nonvs for hibernation to work. To allow the affected systems to avoid saving and restoring the NVS area during suspend to RAM and resume, introduce kernel command line option acpi_sleep=nonvs and make acpi_sleep=s4_nonvs work as its alias temporarily (add acpi_sleep=s4_nonvs to the feature removal file). Addresses https://bugzilla.kernel.org/show_bug.cgi?id=16396 . Signed-off-by: Rafael J. Wysocki Reported-and-tested-by: tomas m Signed-off-by: Len Brown --- Documentation/feature-removal-schedule.txt | 7 +++++++ Documentation/kernel-parameters.txt | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index c268783bc4e7..1571c0c83dba 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -647,3 +647,10 @@ Who: Stefan Richter ---------------------------- +What: The acpi_sleep=s4_nonvs command line option +When: 2.6.37 +Files: arch/x86/kernel/acpi/sleep.c +Why: superseded by acpi_sleep=nonvs +Who: Rafael J. Wysocki + +---------------------------- diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 4ddb58df081e..2b2407d9a6d0 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -254,8 +254,8 @@ and is between 256 and 4096 characters. It is defined in the file control method, with respect to putting devices into low power states, to be enforced (the ACPI 2.0 ordering of _PTS is used by default). - s4_nonvs prevents the kernel from saving/restoring the - ACPI NVS memory during hibernation. + nonvs prevents the kernel from saving/restoring the + ACPI NVS memory during suspend/hibernation and resume. sci_force_enable causes the kernel to set SCI_EN directly on resume from S1/S3 (which is against the ACPI spec, but some broken systems don't work without it). -- cgit From a64afb057b607c04383ab5fb53c51421ba18c434 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 20 Jul 2010 17:50:52 +1000 Subject: xfs: remove obsolete osyncisosync mount option Since Linux 2.6.33 the kernel has support for real O_SYNC, which made the osyncisosync option a no-op. Warn the users about this and remove the mount flag for it. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- Documentation/filesystems/xfs.txt | 11 ----------- 1 file changed, 11 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/xfs.txt b/Documentation/filesystems/xfs.txt index 9878f50d6ed6..7bff3e4f35df 100644 --- a/Documentation/filesystems/xfs.txt +++ b/Documentation/filesystems/xfs.txt @@ -131,17 +131,6 @@ When mounting an XFS filesystem, the following options are accepted. Don't check for double mounted file systems using the file system uuid. This is useful to mount LVM snapshot volumes. - osyncisosync - Make O_SYNC writes implement true O_SYNC. WITHOUT this option, - Linux XFS behaves as if an "osyncisdsync" option is used, - which will make writes to files opened with the O_SYNC flag set - behave as if the O_DSYNC flag had been used instead. - This can result in better performance without compromising - data safety. - However if this option is not in effect, timestamp updates from - O_SYNC writes can be lost if the system crashes. - If timestamp updates are critical, use the osyncisosync option. - uquota/usrquota/uqnoenforce/quota User disk quota accounting enabled, and limits (optionally) enforced. Refer to xfs_quota(8) for further details. -- cgit From 1dbd30e9890fd69e50b17edd70ca583546b0fe4e Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Mon, 12 Jul 2010 21:53:28 +0100 Subject: ARM: 6225/1: make TCM allocation static and common for all archs This changes the TCM handling so that a fixed area is reserved at 0xfffe0000-0xfffeffff for TCM. This areas is used by XScale but XScale does not have TCM so the mechanisms are mutually exclusive. This change is needed to make TCM detection more dynamic while still being able to compile code into it, and is a must for the unified ARM goals: the current TCM allocation at different places in memory for each machine would be a nightmare if you want to compile a single image for more than one machine with TCM so it has to be nailed down in one place. Signed-off-by: Linus Walleij Signed-off-by: Russell King --- Documentation/arm/memory.txt | 8 +++++++- Documentation/arm/tcm.txt | 30 +++++++++++++++++++----------- 2 files changed, 26 insertions(+), 12 deletions(-) (limited to 'Documentation') diff --git a/Documentation/arm/memory.txt b/Documentation/arm/memory.txt index eb0fae18ffb1..771d48d3b335 100644 --- a/Documentation/arm/memory.txt +++ b/Documentation/arm/memory.txt @@ -33,7 +33,13 @@ ffff0000 ffff0fff CPU vector page. fffe0000 fffeffff XScale cache flush area. This is used in proc-xscale.S to flush the whole data - cache. Free for other usage on non-XScale. + cache. (XScale does not have TCM.) + +fffe8000 fffeffff DTCM mapping area for platforms with + DTCM mounted inside the CPU. + +fffe0000 fffe7fff ITCM mapping area for platforms with + ITCM mounted inside the CPU. fff00000 fffdffff Fixmap mapping region. Addresses provided by fix_to_virt() will be located here. diff --git a/Documentation/arm/tcm.txt b/Documentation/arm/tcm.txt index 77fd9376e6d7..7c15871c1885 100644 --- a/Documentation/arm/tcm.txt +++ b/Documentation/arm/tcm.txt @@ -19,8 +19,8 @@ defines a CPUID_TCM register that you can read out from the system control coprocessor. Documentation from ARM can be found at http://infocenter.arm.com, search for "TCM Status Register" to see documents for all CPUs. Reading this register you can -determine if ITCM (bit 0) and/or DTCM (bit 16) is present in the -machine. +determine if ITCM (bits 1-0) and/or DTCM (bit 17-16) is present +in the machine. There is further a TCM region register (search for "TCM Region Registers" at the ARM site) that can report and modify the location @@ -35,7 +35,15 @@ The TCM memory can then be remapped to another address again using the MMU, but notice that the TCM if often used in situations where the MMU is turned off. To avoid confusion the current Linux implementation will map the TCM 1 to 1 from physical to virtual -memory in the location specified by the machine. +memory in the location specified by the kernel. Currently Linux +will map ITCM to 0xfffe0000 and on, and DTCM to 0xfffe8000 and +on, supporting a maximum of 32KiB of ITCM and 32KiB of DTCM. + +Newer versions of the region registers also support dividing these +TCMs in two separate banks, so for example an 8KiB ITCM is divided +into two 4KiB banks with its own control registers. The idea is to +be able to lock and hide one of the banks for use by the secure +world (TrustZone). TCM is used for a few things: @@ -65,18 +73,18 @@ in . Using this interface it is possible to: memory. Such a heap is great for things like saving device state when shutting off device power domains. -A machine that has TCM memory shall select HAVE_TCM in -arch/arm/Kconfig for itself, and then the -rest of the functionality will depend on the physical -location and size of ITCM and DTCM to be defined in -mach/memory.h for the machine. Code that needs to use -TCM shall #include If the TCM is not located -at the place given in memory.h it will be moved using -the TCM Region registers. +A machine that has TCM memory shall select HAVE_TCM from +arch/arm/Kconfig for itself. Code that needs to use TCM shall +#include Functions to go into itcm can be tagged like this: int __tcmfunc foo(int bar); +Since these are marked to become long_calls and you may want +to have functions called locally inside the TCM without +wasting space, there is also the __tcmlocalfunc prefix that +will make the call relative. + Variables to go into dtcm can be tagged like this: int __tcmdata foo; -- cgit From 8f92054e7ca1d3a3ae50fb42d2253ac8730d9b2a Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 29 Jul 2010 12:45:55 +0100 Subject: CRED: Fix __task_cred()'s lockdep check and banner comment Fix __task_cred()'s lockdep check by removing the following validation condition: lockdep_tasklist_lock_is_held() as commit_creds() does not take the tasklist_lock, and nor do most of the functions that call it, so this check is pointless and it can prevent detection of the RCU lock not being held if the tasklist_lock is held. Instead, add the following validation condition: task->exit_state >= 0 to permit the access if the target task is dead and therefore unable to change its own credentials. Fix __task_cred()'s comment to: (1) discard the bit that says that the caller must prevent the target task from being deleted. That shouldn't need saying. (2) Add a comment indicating the result of __task_cred() should not be passed directly to get_cred(), but rather than get_task_cred() should be used instead. Also put a note into the documentation to enforce this point there too. Signed-off-by: David Howells Acked-by: Jiri Olsa Cc: Paul E. McKenney Signed-off-by: Linus Torvalds --- Documentation/credentials.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation') diff --git a/Documentation/credentials.txt b/Documentation/credentials.txt index a2db35287003..995baf379c07 100644 --- a/Documentation/credentials.txt +++ b/Documentation/credentials.txt @@ -417,6 +417,9 @@ reference on them using: This does all the RCU magic inside of it. The caller must call put_cred() on the credentials so obtained when they're finished with. + [*] Note: The result of __task_cred() should not be passed directly to + get_cred() as this may race with commit_cred(). + There are a couple of convenience functions to access bits of another task's credentials, hiding the RCU magic from the caller: -- cgit