## Automatically generated incremental diff ## From: linux-2.6.12-rc5 ## To: linux-2.6.12-rc6 ## Robot: $Id: make-incremental-diff,v 1.12 2004/01/06 07:19:36 hpa Exp $ diff -urN linux-2.6.12-rc5/Documentation/DocBook/libata.tmpl linux-2.6.12-rc6/Documentation/DocBook/libata.tmpl --- linux-2.6.12-rc5/Documentation/DocBook/libata.tmpl 2005-06-06 11:30:31.154629985 -0700 +++ linux-2.6.12-rc6/Documentation/DocBook/libata.tmpl 2005-06-06 11:30:38.185935308 -0700 @@ -14,7 +14,7 @@ - 2003 + 2003-2005 Jeff Garzik @@ -44,30 +44,38 @@ - - Thanks + + Introduction - The bulk of the ATA knowledge comes thanks to long conversations with - Andre Hedrick (www.linux-ide.org). + libATA is a library used inside the Linux kernel to support ATA host + controllers and devices. libATA provides an ATA driver API, class + transports for ATA and ATAPI devices, and SCSI<->ATA translation + for ATA devices according to the T10 SAT specification. - Thanks to Alan Cox for pointing out similarities - between SATA and SCSI, and in general for motivation to hack on - libata. - - - libata's device detection - method, ata_pio_devchk, and in general all the early probing was - based on extensive study of Hale Landis's probe/reset code in his - ATADRVR driver (www.ata-atapi.com). + This Guide documents the libATA driver API, library functions, library + internals, and a couple sample ATA low-level drivers. libata Driver API + + struct ata_port_operations is defined for every low-level libata + hardware driver, and it controls how the low-level driver + interfaces with the ATA and SCSI layers. + + + FIS-based drivers will hook into the system with ->qc_prep() and + ->qc_issue() high-level hooks. Hardware which behaves in a manner + similar to PCI IDE hardware may utilize several generic helpers, + defining at a bare minimum the bus I/O addresses of the ATA shadow + register blocks. + struct ata_port_operations + Disable ATA port void (*port_disable) (struct ata_port *); @@ -78,6 +86,9 @@ unplug). + + + Post-IDENTIFY device configuration void (*dev_config) (struct ata_port *, struct ata_device *); @@ -88,6 +99,9 @@ issue of SET FEATURES - XFER MODE, and prior to operation. + + + Set PIO/DMA mode void (*set_piomode) (struct ata_port *, struct ata_device *); void (*set_dmamode) (struct ata_port *, struct ata_device *); @@ -108,6 +122,9 @@ ->set_dma_mode() is only called if DMA is possible. + + + Taskfile read/write void (*tf_load) (struct ata_port *ap, struct ata_taskfile *tf); void (*tf_read) (struct ata_port *ap, struct ata_taskfile *tf); @@ -120,6 +137,9 @@ taskfile register values. + + + ATA command execute void (*exec_command)(struct ata_port *ap, struct ata_taskfile *tf); @@ -129,17 +149,37 @@ ->tf_load(), to be initiated in hardware. + + + Per-cmd ATAPI DMA capabilities filter + +int (*check_atapi_dma) (struct ata_queued_cmd *qc); + + + +Allow low-level driver to filter ATA PACKET commands, returning a status +indicating whether or not it is OK to use DMA for the supplied PACKET +command. + + + + + Read specific ATA shadow registers u8 (*check_status)(struct ata_port *ap); -void (*dev_select)(struct ata_port *ap, unsigned int device); +u8 (*check_altstatus)(struct ata_port *ap); +u8 (*check_err)(struct ata_port *ap); - Reads the Status ATA shadow register from hardware. On some - hardware, this has the side effect of clearing the interrupt - condition. + Reads the Status/AltStatus/Error ATA shadow register from + hardware. On some hardware, reading the Status register has + the side effect of clearing the interrupt condition. + + + Select ATA device on bus void (*dev_select)(struct ata_port *ap, unsigned int device); @@ -147,9 +187,13 @@ Issues the low-level hardware command(s) that causes one of N hardware devices to be considered 'selected' (active and - available for use) on the ATA bus. + available for use) on the ATA bus. This generally has no +meaning on FIS-based devices. + + + Reset ATA bus void (*phy_reset) (struct ata_port *ap); @@ -162,17 +206,31 @@ functions ata_bus_reset() or sata_phy_reset() for this hook. + + + Control PCI IDE BMDMA engine void (*bmdma_setup) (struct ata_queued_cmd *qc); void (*bmdma_start) (struct ata_queued_cmd *qc); +void (*bmdma_stop) (struct ata_port *ap); +u8 (*bmdma_status) (struct ata_port *ap); - When setting up an IDE BMDMA transaction, these hooks arm - (->bmdma_setup) and fire (->bmdma_start) the hardware's DMA - engine. +When setting up an IDE BMDMA transaction, these hooks arm +(->bmdma_setup), fire (->bmdma_start), and halt (->bmdma_stop) +the hardware's DMA engine. ->bmdma_status is used to read the standard +PCI IDE DMA Status register. + +These hooks are typically either no-ops, or simply not implemented, in +FIS-based drivers. + + + + + High-level taskfile hooks void (*qc_prep) (struct ata_queued_cmd *qc); int (*qc_issue) (struct ata_queued_cmd *qc); @@ -190,20 +248,26 @@ ->qc_issue is used to make a command active, once the hardware and S/G tables have been prepared. IDE BMDMA drivers use the helper function ata_qc_issue_prot() for taskfile protocol-based - dispatch. More advanced drivers roll their own ->qc_issue - implementation, using this as the "issue new ATA command to - hardware" hook. + dispatch. More advanced drivers implement their own ->qc_issue. + + + Timeout (error) handling void (*eng_timeout) (struct ata_port *ap); - This is a high level error handling function, called from the - error handling thread, when a command times out. +This is a high level error handling function, called from the +error handling thread, when a command times out. Most newer +hardware will implement its own error handling code here. IDE BMDMA +drivers may use the helper function ata_eng_timeout(). + + + Hardware interrupt handling irqreturn_t (*irq_handler)(int, void *, struct pt_regs *); void (*irq_clear) (struct ata_port *); @@ -216,6 +280,9 @@ is quiet. + + + SATA phy read/write u32 (*scr_read) (struct ata_port *ap, unsigned int sc_reg); void (*scr_write) (struct ata_port *ap, unsigned int sc_reg, @@ -227,6 +294,9 @@ if ->phy_reset hook called the sata_phy_reset() helper function. + + + Init and shutdown int (*port_start) (struct ata_port *ap); void (*port_stop) (struct ata_port *ap); @@ -240,15 +310,17 @@ tasks. - ->host_stop() is called when the rmmod or hot unplug process - begins. The hook must stop all hardware interrupts, DMA - engines, etc. - - ->port_stop() is called after ->host_stop(). It's sole function is to release DMA/memory resources, now that they are no longer actively being used. + + ->host_stop() is called after all ->port_stop() calls +have completed. The hook must finalize hardware shutdown, release DMA +and other resources, etc. + + + @@ -279,4 +351,24 @@ !Idrivers/scsi/sata_sil.c + + Thanks + + The bulk of the ATA knowledge comes thanks to long conversations with + Andre Hedrick (www.linux-ide.org), and long hours pondering the ATA + and SCSI specifications. + + + Thanks to Alan Cox for pointing out similarities + between SATA and SCSI, and in general for motivation to hack on + libata. + + + libata's device detection + method, ata_pio_devchk, and in general all the early probing was + based on extensive study of Hale Landis's probe/reset code in his + ATADRVR driver (www.ata-atapi.com). + + + diff -urN linux-2.6.12-rc5/Documentation/cpu-freq/cpufreq-stats.txt linux-2.6.12-rc6/Documentation/cpu-freq/cpufreq-stats.txt --- linux-2.6.12-rc5/Documentation/cpu-freq/cpufreq-stats.txt 1969-12-31 16:00:00.000000000 -0800 +++ linux-2.6.12-rc6/Documentation/cpu-freq/cpufreq-stats.txt 2005-06-06 11:30:38.202936047 -0700 @@ -0,0 +1,128 @@ + + CPU frequency and voltage scaling statictics in the Linux(TM) kernel + + + L i n u x c p u f r e q - s t a t s d r i v e r + + - information for users - + + + Venkatesh Pallipadi + +Contents +1. Introduction +2. Statistics Provided (with example) +3. Configuring cpufreq-stats + + +1. Introduction + +cpufreq-stats is a driver that provices CPU frequency statistics for each CPU. +This statistics is provided in /sysfs as a bunch of read_only interfaces. This +interface (when configured) will appear in a seperate directory under cpufreq +in /sysfs (/devices/system/cpu/cpuX/cpufreq/stats/) for each CPU. +Various statistics will form read_only files under this directory. + +This driver is designed to be independent of any particular cpufreq_driver +that may be running on your CPU. So, it will work with any cpufreq_driver. + + +2. Statistics Provided (with example) + +cpufreq stats provides following statistics (explained in detail below). +- time_in_state +- total_trans +- trans_table + +All the statistics will be from the time the stats driver has been inserted +to the time when a read of a particular statistic is done. Obviously, stats +driver will not have any information about the the frequcny transitions before +the stats driver insertion. + +-------------------------------------------------------------------------------- +:/sys/devices/system/cpu/cpu0/cpufreq/stats # ls -l +total 0 +drwxr-xr-x 2 root root 0 May 14 16:06 . +drwxr-xr-x 3 root root 0 May 14 15:58 .. +-r--r--r-- 1 root root 4096 May 14 16:06 time_in_state +-r--r--r-- 1 root root 4096 May 14 16:06 total_trans +-r--r--r-- 1 root root 4096 May 14 16:06 trans_table +-------------------------------------------------------------------------------- + +- time_in_state +This gives the amount of time spent in each of the frequencies supported by +this CPU. The cat output will have "