diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index 488dd4a4945b..b7b1482f6e04 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -119,7 +119,7 @@ X!Ilib/string.c !Elib/string.c Bit Operations -!Iinclude/asm-x86/bitops_32.h +!Iinclude/asm-x86/bitops.h @@ -645,4 +645,58 @@ X!Idrivers/video/console/fonts.c !Edrivers/i2c/i2c-core.c + + Clock Framework + + + The clock framework defines programming interfaces to support + software management of the system clock tree. + This framework is widely used with System-On-Chip (SOC) platforms + to support power management and various devices which may need + custom clock rates. + Note that these "clocks" don't relate to timekeeping or real + time clocks (RTCs), each of which have separate frameworks. + These struct clk instances may be used + to manage for example a 96 MHz signal that is used to shift bits + into and out of peripherals or busses, or otherwise trigger + synchronous state machine transitions in system hardware. + + + + Power management is supported by explicit software clock gating: + unused clocks are disabled, so the system doesn't waste power + changing the state of transistors that aren't in active use. + On some systems this may be backed by hardware clock gating, + where clocks are gated without being disabled in software. + Sections of chips that are powered but not clocked may be able + to retain their last state. + This low power state is often called a retention + mode. + This mode still incurs leakage currents, especially with finer + circuit geometries, but for CMOS circuits power is mostly used + by clocked state changes. + + + + Power-aware drivers only enable their clocks when the device + they manage is in active use. Also, system sleep states often + differ according to which clock domains are active: while a + "standby" state may allow wakeup from several active domains, a + "mem" (suspend-to-RAM) state may require a more wholesale shutdown + of clocks derived from higher speed PLLs and oscillators, limiting + the number of possible wakeup event sources. A driver's suspend + method may need to be aware of system-specific clock constraints + on the target sleep state. + + + + Some platforms support programmable clock generators. These + can be used by external chips of various kinds, such as other + CPUs, multimedia codecs, and devices with strict requirements + for interface clocking. + + +!Iinclude/linux/clk.h + + diff --git a/Documentation/fb/gxfb.txt b/Documentation/fb/gxfb.txt new file mode 100644 index 000000000000..2f640903bbb2 --- /dev/null +++ b/Documentation/fb/gxfb.txt @@ -0,0 +1,52 @@ +[This file is cloned from VesaFB/aty128fb] + +What is gxfb? +================= + +This is a graphics framebuffer driver for AMD Geode GX2 based processors. + +Advantages: + + * No need to use AMD's VSA code (or other VESA emulation layer) in the + BIOS. + * It provides a nice large console (128 cols + 48 lines with 1024x768) + without using tiny, unreadable fonts. + * You can run XF68_FBDev on top of /dev/fb0 + * Most important: boot logo :-) + +Disadvantages: + + * graphic mode is slower than text mode... + + +How to use it? +============== + +Switching modes is done using gxfb.mode_option=... boot +parameter or using `fbset' program. + +See Documentation/fb/modedb.txt for more information on modedb +resolutions. + + +X11 +=== + +XF68_FBDev should generally work fine, but it is non-accelerated. + + +Configuration +============= + +You can pass kernel command line options to gxfb with gxfb.