Linux 2.6 sources for MPC852T processor
Hi, I did the following: $ patch -p1
Linux 2.6 sources for MPC852T processor
On Wed, Apr 26, 2006 at 07:32:13PM -0400, Dan Malek wrote: > > On Apr 26, 2006, at 7:50 AM, David Jander wrote: > > > Yes, MPC852T is supported, although I might add that I have been > > using 2.6.14 > > and 2.6.15 sucessfully with our own MPC852T-based board, but 2.6.16 > > did not > > boot and as of today I don't know why, or whether this is an issue > > at all > > with boards other than ours. > > There is a horrible bug in the 8xx TLB miss handler that is in the > 2.6.16 > sources. I don't know when it appeared. Enable the CPU6 Errata > workaround to see if that solves the problem and please report back > to me. I'm working on a solution. Hi Dan, Shame on me! I screwed up. David, can you please try the following patch on top of vanilla v2.6.16? The large TLB change introduced in v2.6.16 (which is broken as is for configurations without CPU6 errata enabled as Dan noted) should boost performance significantly, so you might want to rerun the lmbench tests... diff --git a/arch/ppc/kernel/head_8xx.S b/arch/ppc/kernel/head_8xx.S index ec53c7d..7a2f205 100644 --- a/arch/ppc/kernel/head_8xx.S +++ b/arch/ppc/kernel/head_8xx.S @@ -355,9 +355,7 @@ #endif . = 0x1200 DataStoreTLBMiss: -#ifdef CONFIG_8xx_CPU6 stw r3, 8(r0) -#endif DO_8xx_CPU6(0x3f80, r3) mtspr SPRN_M_TW, r10 /* Save a couple of working registers */ mfcrr10 @@ -417,9 +415,7 @@ #endif lwz r11, 0(r0) mtcrr11 lwz r11, 4(r0) -#ifdef CONFIG_8xx_CPU6 lwz r3, 8(r0) -#endif rfi /* This is an instruction TLB error on the MPC8xx. This could be due
Linux 2.6 sources for MPC852T processor
On Thursday 27 April 2006 01:32, Dan Malek wrote: > There is a horrible bug in the 8xx TLB miss handler that is in the > 2.6.16 > sources. I don't know when it appeared. Enable the CPU6 Errata > workaround to see if that solves the problem and please report back > to me. I'm working on a solution. I received instructions from Marcelo to reverse two patches he sent me this morning, that did solve the problem. In fact those patches changed some TLB-related assembly code in head_8xx.S Greetings, -- David Jander
Linux 2.6 sources for MPC852T processor
On Apr 26, 2006, at 7:50 AM, David Jander wrote: > Yes, MPC852T is supported, although I might add that I have been > using 2.6.14 > and 2.6.15 sucessfully with our own MPC852T-based board, but 2.6.16 > did not > boot and as of today I don't know why, or whether this is an issue > at all > with boards other than ours. There is a horrible bug in the 8xx TLB miss handler that is in the 2.6.16 sources. I don't know when it appeared. Enable the CPU6 Errata workaround to see if that solves the problem and please report back to me. I'm working on a solution. Thanks. -- Dan
Linux 2.6 sources for MPC852T processor
On Wednesday 26 April 2006 11:50, Chandrasekhar Nagaraj wrote: > Hi, > I have a customized board based on the MPC852T based processor. > I intend to develop a BSP for this board. > > Does 2.6.16 from the kernel.org support this processor? First of all, please avoid HTML in e-mail messages. It is hard to read, and normally banned on mailing list such as this one. Yes, MPC852T is supported, although I might add that I have been using 2.6.14 and 2.6.15 sucessfully with our own MPC852T-based board, but 2.6.16 did not boot and as of today I don't know why, or whether this is an issue at all with boards other than ours. > > In the 2.6.16 sources I found support for CONFIG_8xx. Does this mean > that 852T processor is also supported? Yes. Look at BSP stuff for other 8xx boards to learn how to port yours. Keep an eye on the new platform_bus stuff, that's currently being implemented for different drivers and subsystmes for powerpc (this could be the reason, our own BSP stuff stopped working with 2.6.16, btw). Also a transition from /arch/ppc and /arch/ppc64 towards the common /arch/powerpc is in progress, and therefore some things might be in a state of flux between released versions of the kernel. As of today (kernel 2.6.16) the architecture you need to use is still /arch/ppc. Good luck! Greetings, -- David Jander
Linux 2.6 sources for MPC852T processor
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