From 229ea9289f986fdfafe14d48cbe6aaefb4cb9f4a Mon Sep 17 00:00:00 2001 From: Matt Porter Date: Mon, 18 Oct 2004 08:57:39 -0700 Subject: [PATCH] [PATCH] ppc32: configure PPC440GX L2 cache based on CPU rev This patch enables/disables the PPC440GX L2 cache based on errata which prevents reliable operation on certain CPU revisions and speed grades. Signed-off-by: Eugene Surovegin Signed-off-by: Matt Porter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ppc/platforms/4xx/ocotea.c | 24 ++++++++++++------------ arch/ppc/syslib/ibm440gx_common.c | 13 +++++++++++++ arch/ppc/syslib/ibm440gx_common.h | 5 ++++- 3 files changed, 29 insertions(+), 13 deletions(-) diff --git a/arch/ppc/platforms/4xx/ocotea.c b/arch/ppc/platforms/4xx/ocotea.c index 6d4a3b9ef6697..13fa0acce91db 100644 --- a/arch/ppc/platforms/4xx/ocotea.c +++ b/arch/ppc/platforms/4xx/ocotea.c @@ -81,7 +81,7 @@ ocotea_show_cpuinfo(struct seq_file *m) { seq_printf(m, "vendor\t\t: IBM\n"); seq_printf(m, "machine\t\t: PPC440GX EVB (Ocotea)\n"); - + ibm440gx_show_cpuinfo(m); return 0; } @@ -299,15 +299,6 @@ ocotea_setup_arch(void) mtspr(SPRN_DBCR0, (DBCR0_TDE | DBCR0_IDM)); #endif - /* - * Determine various clocks. - * To be completely correct we should get SysClk - * from FPGA, because it can be changed by on-board switches - * --ebs - */ - ibm440gx_get_clocks(&clocks, 33333333, 6 * 1843200); - ocp_sys_info.opb_bus_freq = clocks.opb; - /* Setup TODC access */ TODC_INIT(TODC_TYPE_DS1743, 0, @@ -350,8 +341,17 @@ void __init platform_init(unsigned long r3, unsigned long r4, if (r3) __res = *(bd_t *)(r3 + KERNELBASE); - /* Disable L2-Cache due to hardware issues */ - ibm440gx_l2c_disable(); + /* + * Determine various clocks. + * To be completely correct we should get SysClk + * from FPGA, because it can be changed by on-board switches + * --ebs + */ + ibm440gx_get_clocks(&clocks, 33333333, 6 * 1843200); + ocp_sys_info.opb_bus_freq = clocks.opb; + + /* Disable L2-Cache on broken hardware, enable it otherwise */ + ibm440gx_l2c_setup(&clocks); ibm44x_platform_init(); diff --git a/arch/ppc/syslib/ibm440gx_common.c b/arch/ppc/syslib/ibm440gx_common.c index 5da7bca6b4207..caccc9765e0f1 100644 --- a/arch/ppc/syslib/ibm440gx_common.c +++ b/arch/ppc/syslib/ibm440gx_common.c @@ -171,6 +171,19 @@ void __init ibm440gx_l2c_disable(void){ asm volatile ("sync; isync" ::: "memory"); } +void __init ibm440gx_l2c_setup(struct ibm44x_clocks* p) +{ + /* Disable L2C on rev.A, rev.B and 800MHz version of rev.C, + enable it on all other revisions + */ + u32 pvr = mfspr(PVR); + if (pvr == PVR_440GX_RA || pvr == PVR_440GX_RB || + (pvr == PVR_440GX_RC && p->cpu > 667000000)) + ibm440gx_l2c_disable(); + else + ibm440gx_l2c_enable(); +} + int __init ibm440gx_get_eth_grp(void) { return (SDR_READ(DCRN_SDR_PFC1) & DCRN_SDR_PFC1_EPS) >> DCRN_SDR_PFC1_EPS_SHIFT; diff --git a/arch/ppc/syslib/ibm440gx_common.h b/arch/ppc/syslib/ibm440gx_common.h index 5dbca9896f50d..e73aa0411d358 100644 --- a/arch/ppc/syslib/ibm440gx_common.h +++ b/arch/ppc/syslib/ibm440gx_common.h @@ -4,7 +4,7 @@ * PPC440GX system library * * Eugene Surovegin or - * Copyright (c) 2003 Zultys Technologies + * Copyright (c) 2003, 2004 Zultys Technologies * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the @@ -37,6 +37,9 @@ void ibm440gx_l2c_enable(void) __init; /* Disable L2 cache */ void ibm440gx_l2c_disable(void) __init; +/* Enable/disable L2 cache for a particular chip revision */ +void ibm440gx_l2c_setup(struct ibm44x_clocks*) __init; + /* Get Ethernet Group */ int ibm440gx_get_eth_grp(void) __init; -- 2.53.0