Re: [LinuxBIOS] v3: documentation fixes

[Jordan Crouse]

I think printk is always available - any previous printk pain has been
(finally) resolved.

On 15/11/07 01:25 +0100, Carl-Daniel Hailfinger wrote:
> Fix code comments/documentation related to printk.
> Sprinkle TODOs all over obviously wrong comments.
> Document possible execution flow alternatives for later investigation.
>
> Signed-off-by: Carl-Daniel Hailfinger
> Index: LinuxBIOSv3/mainboard/adl/msm800sev/stage1.c
>
> --- LinuxBIOSv3/mainboard/adl/msm800sev/stage1.c	(Revision 509)
> +++ LinuxBIOSv3/mainboard/adl/msm800sev/stage1.c	(Arbeitskopie)
> @@ -51,5 +51,5 @@
>     */
>    cs5536_disable_internal_uart();
>    w83627hf_enable_serial(0x2e, SERIAL_DEV, SERIAL_IOBASE);
> printk(BIOS_DEBUG, "Done %s\n", __FUNCTION__);
> /* We can NOT yet use printk! */
>
> }
> Index: LinuxBIOSv3/mainboard/emulation/qemu-x86/stage1.c
> ===================================================================
> --- LinuxBIOSv3/mainboard/emulation/qemu-x86/stage1.c	(Revision 509)
> +++ LinuxBIOSv3/mainboard/emulation/qemu-x86/stage1.c	(Arbeitskopie)
> @@ -17,7 +17,7 @@
> Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
>
> */
>
> -/* no printk allowed until hardware is ready; hardware is ready */
> +/* no printk allowed until hardware is ready; hardware is not yet ready */
>
> /**
> start up hardware needed for stage1
> Index: LinuxBIOSv3/lib/stage2.c
>
> --- LinuxBIOSv3/lib/stage2.c	(Revision 509)
> +++ LinuxBIOSv3/lib/stage2.c	(Arbeitskopie)
> @@ -37,7 +37,10 @@
> Device Enumeration: in the dev_enumerate() phase.
> TODO: Check whether this documentation is still correct. Improve it.
> TODO:
> Check whether this documentation is still correct. Improve it.
> Replace magic constants by #defines.
> Fix POST codes. Right now phases 1+3 have POST 0x30, phases 2+4 have 0x40.
> */
>
> int stage2(void)
>  {
> @@ -54,13 +57,19 @@
>
> post_code(0x20);
> /* TODO: Explain why we use printk here although it is impossible */
>
> /* TODO: Explain why we use printk here although it is claimed to be
> * impossible according to the documentation. The "has to be done
> * before printk can be used" comment below seems to suggest the same.
> * However, we already enable serial in arch/x86/stage1.c:stage1_main()
> * when we call hardware_stage1(); uart_init(); console_init(); 
> */
>
> printk(BIOS_NOTICE, console_test);
>
> dev_init();
>
> /* Console init, also ANYTHING that has to be done
> * before printk can be used. 
> * before printk can be used.
> * FIXME: This comment contradicts the comment above.
> */
>  post_code(0x30);
>  dev_phase1();
> Index: LinuxBIOSv3/arch/x86/stage1.c
>
> --- LinuxBIOSv3/arch/x86/stage1.c	(Revision 509)
> +++ LinuxBIOSv3/arch/x86/stage1.c	(Arbeitskopie)
> @@ -108,8 +108,12 @@
>
> //
>    uart_init();	// initialize serial port
> console_init(); // print banner
> /* Exactly from now on we can use printk. Celebrate this by printing
> * a LB banner.
> */
> console_init();
> if (bist!=0) {
>   printk(BIOS_INFO, "BIST FAILED: %08x", bist);
>   die("");
>
> @@ -133,6 +137,30 @@
>    // FIXME check integrity
> /* Right now we have to fit
> *   initram stack
> *   lar stack
> * into cache during CAR. IFF we can be sure that
> *   nrv2b stack
> *   initram code
> *   lar code
> * fit into cache as well, we can compress initram code and lar code,
> * leading to potential speedup (due to having to read less from ROM)
> * and size savings. However, initram code and lar code would have
> * to be compiled as PIC code, not as XIP code.
> *
> * Suggested code flow:
> * unrv2b(lar_code);
> * ...
> * execute_in_car(&archive, "normal/initram");
> *
> * A less complicated (from a linker perspective) variant would
> * compress only initram code, but it is not clear whether all hardware
> * can run code from cache while training memory in the area designated
> * by the cache. Some processors might drop cache contents in that case,
> * rendering the ideas above mostly moot.
> * TODO: Check how this works in the real world.
> */
> // find first initram
>  if (check_normal_boot_flag()) {
>   printk(BIOS_DEBUG, "Choosing normal boot.\n");