From: Will Schmidt Date: Tue, 28 Sep 2010 15:33:12 +0000 (+0000) Subject: powerpc/pseries: Add kernel parameter to disable batched hcalls X-Git-Tag: v2.6.38-rc1~405^2~46 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=4e89a2d8e2d5ab33d73b76f16c10fdf515faabef;p=karo-tx-linux.git powerpc/pseries: Add kernel parameter to disable batched hcalls This introduces a pair of kernel parameters that can be used to disable the MULTITCE and BULK_REMOVE h-calls. By default, those hcalls are enabled, active, and good for throughput and performance. The ability to disable them will be useful for some of the PREEMPT_RT related investigation and work occurring on Power. Signed-off-by: Will Schmidt cc: Olof Johansson cc: Anton Blanchard cc: Benjamin Herrenschmidt Signed-off-by: Benjamin Herrenschmidt --- diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index cdd2a6e8a3b7..69bb6a9c871a 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -403,6 +403,10 @@ and is between 256 and 4096 characters. It is defined in the file bttv.pll= See Documentation/video4linux/bttv/Insmod-options bttv.tuner= and Documentation/video4linux/bttv/CARDLIST + bulk_remove=off [PPC] This parameter disables the use of the pSeries + firmware feature for flushing multiple hpte entries + at a time. + c101= [NET] Moxa C101 synchronous serial card cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection. @@ -1490,6 +1494,10 @@ and is between 256 and 4096 characters. It is defined in the file mtdparts= [MTD] See drivers/mtd/cmdlinepart.c. + multitce=off [PPC] This parameter disables the use of the pSeries + firmware feature for updating multiple TCE entries + at a time. + onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration Format: [die0_boundary][,die0_lock][,die1_boundary][,die1_lock] diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index a77bcaed80af..fa2906a103dd 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -622,3 +622,17 @@ void iommu_init_early_pSeries(void) set_pci_dma_ops(&dma_iommu_ops); } +static int __init disable_multitce(char *str) +{ + if (strcmp(str, "off") == 0 && + firmware_has_feature(FW_FEATURE_LPAR) && + firmware_has_feature(FW_FEATURE_MULTITCE)) { + printk(KERN_INFO "Disabling MULTITCE firmware feature\n"); + ppc_md.tce_build = tce_build_pSeriesLP; + ppc_md.tce_free = tce_free_pSeriesLP; + powerpc_firmware_features &= ~FW_FEATURE_MULTITCE; + } + return 1; +} + +__setup("multitce=", disable_multitce); diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index f129040d974c..5d3ea9f60dd7 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -627,6 +627,18 @@ static void pSeries_lpar_flush_hash_range(unsigned long number, int local) spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags); } +static int __init disable_bulk_remove(char *str) +{ + if (strcmp(str, "off") == 0 && + firmware_has_feature(FW_FEATURE_BULK_REMOVE)) { + printk(KERN_INFO "Disabling BULK_REMOVE firmware feature"); + powerpc_firmware_features &= ~FW_FEATURE_BULK_REMOVE; + } + return 1; +} + +__setup("bulk_remove=", disable_bulk_remove); + void __init hpte_init_lpar(void) { ppc_md.hpte_invalidate = pSeries_lpar_hpte_invalidate;