From e02c521d94b45d7b05aa522e4ccde6b74bf5fe57 Mon Sep 17 00:00:00 2001 From: Stefan Roese Date: Wed, 9 Jan 2008 10:23:16 +0100 Subject: [PATCH] ppc4xx: Add 44x cache locking to better support init-ram in d-cache This patch adds support for locking the init-ram/stack in d-cache, so that other regions may use d-cache as well Note, that this current implementation locks exactly 4k of d-cache, so please make sure that you don't define a bigger init-ram area. Take a look at the lwmon5 440EPx implementation as a reference. Signed-off-by: Stefan Roese --- cpu/ppc4xx/start.S | 52 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/cpu/ppc4xx/start.S b/cpu/ppc4xx/start.S index 52601ed700..a730604367 100644 --- a/cpu/ppc4xx/start.S +++ b/cpu/ppc4xx/start.S @@ -636,6 +636,33 @@ _start: dcbz r0,r3 addi r3,r3,32 bdnz ..d_ag + + /* + * Lock the init-ram/stack in d-cache, so that other regions + * may use d-cache as well + * Note, that this current implementation locks exactly 4k + * of d-cache, so please make sure that you don't define a + * bigger init-ram area. Take a look at the lwmon5 440EPx + * implementation as a reference. + */ + msync + isync + /* 8. set TFLOOR/NFLOOR to 8 (-> 8*16*32 bytes locked -> 4k) */ + lis r1,0x0201 + ori r1,r1,0xf808 + mtspr dvlim,r1 + lis r1,0x0808 + ori r1,r1,0x0808 + mtspr dnv0,r1 + mtspr dnv1,r1 + mtspr dnv2,r1 + mtspr dnv3,r1 + mtspr dtv0,r1 + mtspr dtv1,r1 + mtspr dtv2,r1 + mtspr dtv3,r1 + msync + isync #endif /* CFG_INIT_RAM_DCACHE */ /* 440EP & 440GR are only 440er PPC's without internal SRAM */ @@ -1345,6 +1372,31 @@ relocate_code: mr r4,r10 mr r5,r11 #endif + +#ifdef CFG_INIT_RAM_DCACHE + /* + * Unlock the previously locked d-cache + */ + msync + isync + /* set TFLOOR/NFLOOR to 0 again */ + lis r6,0x0001 + ori r6,r6,0xf800 + mtspr dvlim,r6 + lis r6,0x0000 + ori r6,r6,0x0000 + mtspr dnv0,r6 + mtspr dnv1,r6 + mtspr dnv2,r6 + mtspr dnv3,r6 + mtspr dtv0,r6 + mtspr dtv1,r6 + mtspr dtv2,r6 + mtspr dtv3,r6 + msync + isync +#endif /* CFG_INIT_RAM_DCACHE */ + #if defined(CONFIG_440EP) || defined(CONFIG_440GR) || \ defined(CONFIG_440EPX) || defined(CONFIG_440GRX) || \ defined(CONFIG_440SP) || defined(CONFIG_440SPE) -- 2.25.1