Re: [PATCH] bios: Makefile ACPI DSDT generation

[Avi Kivity <avi@qumranet.com>]

Alex Williamson wrote:
> Hi Avi,
>
> This builds on your preprocessor work for cleaning up the DSDT and makes
> it trivially easy to change the CPU and PCI hotplug slot count.  I'm
> thinking about splitting a few SSDTs out of the monolithic DSDT, and
> generating some of the code at compile time should make that easier.
> This generates the same ASL after the preprocessor as current code.
> BTW, isn't \_PR.PRU & \_PR.PRD too small for hotplug'ing more than 8
> CPUs?  Let me know what you think.  Thanks,
>
> 	Alex
>
>
>
> kvm: bios: generate cpu and pci hotplug objects at compile time
>
> Signed-off-by: Alex Williamson <alex.williamson@hp.com>
> --
>
> diff --git a/bios/Makefile b/bios/Makefile
> index 48022ea..8ca5482 100644
> --- a/bios/Makefile
> +++ b/bios/Makefile
> @@ -22,6 +22,9 @@
>  
>  # Makefile for the BIOS component of bochs
>  
> +max_cpus ?= 16
> +max_pci_slots ?= 32
> +win2k_cpu_limit ?= y
>   

I don't particularly like random environment variables influencing the 
build.  This should be part of ./configure.

>  
>  
> +acpi-dsdt-processor.gen:
> +	rm -f $@;
> +	last=`expr $(max_cpus) - 1`;					\
> +	if [ "$(win2k_cpu_limit)" = "y" ] && [ $$last -gt 14 ]; then	\
> +		last=14;						\
> +	fi;								\
> +	for i in `seq 1 $$last`; do					\
> +		echo "gen_processor($$i, `printf "%X" $$i`)" >> $@;	\
> +	done
> +
> +acpi-dsdt-cpu-hotplug.gen:
> +	rm -f $@;
> +	last=`expr $(max_cpus) - 1`;					\
> +	if [ "$(win2k_cpu_limit)" = "y" ] && [ $$last -gt 14 ]; then	\
> +		last=14;						\
> +	fi;								\
> +	for i in `seq 1 $$last`; do					\
> +		echo "gen_cpu_hotplug($$i, `printf "%X" $$i`)" >> $@;	\
> +	done
> +
> +acpi-dsdt-prt-slot.gen:
> +	rm -f $@;
> +	last=`expr $(max_pci_slots) - 1`;				\
> +	for i in `seq 0 4 $$last`; do					\
> +		echo "prt_slot0(`printf "0x%04x" $$i`)," >> $@;		\
> +		next=`expr $$i + 1`;					\
> +		echo "prt_slot1(`printf "0x%04x" $$next`)," >> $@;	\
> +		next=`expr $$i + 2`;					\
> +		echo "prt_slot2(`printf "0x%04x" $$next`)," >> $@;	\
> +		next=`expr $$i + 3`;					\
> +		echo "prt_slot3(`printf "0x%04x" $$next`)," >> $@;	\
> +	done
> +
> +acpi-dsdt-hotplug-slot.gen:
> +	rm -f $@;
> +	last=`expr $(max_pci_slots) - 1`;				\
> +	for i in `seq 1 $$last`; do					\
> +		echo "hotplug_slot($$i, `printf "0x%04x" $$i`)" >> $@;	\
> +	done
> +
> +acpi-dsdt-pci-hotplug.gen:
> +	rm -f $@;
> +	last=`expr $(max_pci_slots) - 1`;				\
> +	for i in `seq 1 $$last`; do					\
> +		echo "gen_pci_hotplug($$i)" >> $@;			\
> +	done
> +
>   

Moving so much code into the Makefile isn't so pretty either.  I 
considered using a preprocessor other than cpp, but then nobody knows 
how to work with things like m4.

Ideas, anyone?

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.