Re: [PATCH -queue v0 1/6] [loongson] add basic loongson-2f support

[Arnaud Patard <apatard@mandriva.com>]

Hi,

Wu Zhangjin <wuzhangjin@gmail.com> writes:

> Loongson2F has built-in DDR2 and PCIX controller. The PCIX controller
> have a similar programming interface with FPGA northbridge used in
> Loongson2E.
>
> The main differences between loongson-2e and loongson-2f include:
>
> 1. loongson-2f has an extra address windows configuration module, which
> can be used to map CPU address space to DDR or PCI address space, or map
> the PCI-DMA address space to DDR or LIO address space.
>
> 2. loongson-2f support 8 levels of software configurable cpu frequency,
> which can be configured via a register(LOONGSON_CHIPCFG0).  the coming
> cpufreq and standby support are based on this feature.
>
> herein, the module and the corresponding operations are abstracted to
> loongson.h.
>
> besides, the other loongson2f-specific source code are added here,
> including gcc 4.4 support, pci memory space, pci io space, dma address.
>
> Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
> ---
>  arch/mips/Kconfig                                  |   18 ++++
>  arch/mips/Makefile                                 |    2 +
>  .../mips/include/asm/mach-loongson/dma-coherence.h |    4 +
>  arch/mips/include/asm/mach-loongson/loongson.h     |   84 +++++++++++++++++++-
>  arch/mips/include/asm/mach-loongson/mem.h          |   25 ++++--
>  arch/mips/include/asm/mach-loongson/pci.h          |   28 ++++++-
>  arch/mips/loongson/common/bonito-irq.c             |    5 +
>  arch/mips/loongson/common/init.c                   |   18 ++++
>  arch/mips/loongson/common/mem.c                    |   17 ++++
>  arch/mips/loongson/common/pci.c                    |    8 ++
>  10 files changed, 199 insertions(+), 10 deletions(-)
>
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index ae9fa98..8417357 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -1059,6 +1059,21 @@ config CPU_LOONGSON2E
>  	  The Loongson 2E processor implements the MIPS III instruction set
>  	  with many extensions.
>  
> +	  It has an internal FPGA northbridge, which is compatiable to
> +	  bonito64.
> +
> +config CPU_LOONGSON2F
> +	bool "Loongson 2F"
> +	depends on SYS_HAS_CPU_LOONGSON2F
> +	select CPU_LOONGSON2
> +	help
> +	  The Loongson 2F processor implements the MIPS III instruction set
> +	  with many extensions.
> +
> +	  Loongson2F have built-in DDR2 and PCIX controller. The PCIX controller
> +	  have a similar programming interface with FPGA northbridge used in
> +	  Loongson2E.
> +

Small question : Why don't you restrict to 64bit kernels only ? From
what I remember from some discussions with ST, trying to use a 32-bit
kernel on 2f is a nice way to get troubles. It would be better imho to
forbid such a configuration. As a side effect, this will remove all
'defined(CONFIG_64BIT)' parts of your #ifdef tests. 

Arnaud