From 245a7868d2f2e54a9a9b084de00d003a9badb2a5 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Mon, 14 Apr 2014 12:04:27 +0100 Subject: MIPS: smp-cps: rework core/VPE initialisation When hotplug and/or a powered down idle state are supported cases will arise where a non-zero VPE must be brought online without VPE 0, and it where multiple VPEs must be onlined simultaneously. This patch prepares for that by: - Splitting struct boot_config into core & VPE boot config structures, allocated one per core or VPE respectively. This allows for multiple VPEs to be onlined simultaneously without clobbering each others configuration. - Indicating which VPEs should be online within a core at any given time using a bitmap. This allows multiple VPEs to be brought online simultaneously and also indicates to VPE 0 whether it should halt after starting any non-zero VPEs that should be online within the core. For example if all VPEs within a core are offlined via hotplug and the user onlines the second VPE within that core: 1) The core will be powered up. 2) VPE 0 will run from the BEV (ie. mips_cps_core_entry) to initialise the core. 3) VPE 0 will start VPE 1 because its bit is set in the cores bitmap. 4) VPE 0 will halt itself because its bit is clear in the cores bitmap. - Moving the core & VPE initialisation to assembly code which does not make any use of the stack. This is because if a non-zero VPE is to be brought online in a powered down core then when VPE 0 of that core runs it may not have a valid stack, and even if it did then it's messy to run through parts of generic kernel code on VPE 0 before starting the correct VPE. Signed-off-by: Paul Burton --- arch/mips/include/asm/smp-cps.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'arch/mips/include') diff --git a/arch/mips/include/asm/smp-cps.h b/arch/mips/include/asm/smp-cps.h index d60d1a2..d49279e 100644 --- a/arch/mips/include/asm/smp-cps.h +++ b/arch/mips/include/asm/smp-cps.h @@ -13,17 +13,23 @@ #ifndef __ASSEMBLY__ -struct boot_config { - unsigned int core; - unsigned int vpe; +struct vpe_boot_config { unsigned long pc; unsigned long sp; unsigned long gp; }; -extern struct boot_config mips_cps_bootcfg; +struct core_boot_config { + atomic_t vpe_mask; + struct vpe_boot_config *vpe_config; +}; + +extern struct core_boot_config *mips_cps_core_bootcfg; extern void mips_cps_core_entry(void); +extern void mips_cps_core_init(void); + +extern struct vpe_boot_config *mips_cps_boot_vpes(void); #else /* __ASSEMBLY__ */ -- cgit v1.1