public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: Martyn Welch <martyn.welch@ge•com>
To: Scott Wood <scottwood@freescale•com>
Cc: linuxppc-dev@lists•ozlabs.org
Subject: Re: [PATCH] PowerPC: Remove hardcoded BAT configuration of IMMR in CPM	early debug console
Date: Wed, 02 Jun 2010 09:06:16 +0100	[thread overview]
Message-ID: <4C0610F8.6020801@ge.com> (raw)
In-Reply-To: <4C053008.50306@freescale.com>

Scott Wood wrote:
> On 06/01/2010 08:43 AM, Martyn Welch wrote:
>>>>> diff --git a/arch/powerpc/kernel/head_32.S
>>>>> b/arch/powerpc/kernel/head_32.S
>>>>> index e025e89..861cace 100644
>>>>> --- a/arch/powerpc/kernel/head_32.S
>>>>> +++ b/arch/powerpc/kernel/head_32.S
>>>>> @@ -1194,12 +1194,13 @@ setup_disp_bat:
>>>>>    #endif /* CONFIG_BOOTX_TEXT */
>>>>>
>>>>>    #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
>>>>> +#define PPC_EARLY_DEBUG_CPM_ADDR
>>>>> ASM_CONST(CONFIG_PPC_EARLY_DEBUG_CPM_ADDR)
>>>>>    setup_cpm_bat:
>>>>> -    lis    r8, 0xf000
>>>>> +    lis    r8, PPC_EARLY_DEBUG_CPM_ADDR@ha
>>>>>        ori    r8, r8,    0x002a
>>>>>        mtspr    SPRN_DBAT1L, r8
>>>>>
>>>>> -    lis    r11, 0xf000
>>>>> +    lis    r11, PPC_EARLY_DEBUG_CPM_ADDR@ha
>>>>>        ori    r11, r11, (BL_1M<<  2) | 2
>>>>>        mtspr    SPRN_DBAT1U, r11
>>>>>
>>>> Only the physical address should depend on where IMMR is.  We should
>>>> use fixmap instead of an arbitrary address for the effective address.
>>>> There's a existing FIX_EARLY_DEBUG_BASE, but it's only 128 KiB so
>>>> we'll have to either grow it, or map only a subset of IMMR.
>>>>
>>>>
>>>
>>> I think that's a more fundamental change to CPM early debug than I can
>>> handle right now.
>
> Is IMMRBASE on your board at some address that has a low likelihood of
> conflicting when treated as a kernel effective address?

It's at 0x0f000000, is seems ok, but then I'm not sure I fully
understand kernel effective addresses.

Martyn

-- 
Martyn Welch (Principal Software Engineer)   |   Registered in England and
GE Intelligent Platforms                     |   Wales (3828642) at 100
T +44(0)127322748                            |   Barbirolli Square, Manchester,
E martyn.welch@ge•com                        |   M2 3AB  VAT:GB 927559189

  reply	other threads:[~2010-06-02  8:06 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-05-28 15:18 [PATCH] PowerPC: Remove hardcoded BAT configuration of IMMR in CPM early debug console Martyn Welch
2010-05-28 16:18 ` Scott Wood
2010-05-29  3:37   ` Benjamin Herrenschmidt
2010-06-01 12:52   ` Martyn Welch
2010-06-01 13:43     ` Martyn Welch
2010-06-01 16:06       ` Scott Wood
2010-06-02  8:06         ` Martyn Welch [this message]
2010-06-02 16:28           ` Scott Wood
2010-06-03  9:12             ` Martyn Welch

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4C0610F8.6020801@ge.com \
    --to=martyn.welch@ge$(echo .)com \
    --cc=linuxppc-dev@lists$(echo .)ozlabs.org \
    --cc=scottwood@freescale$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox