- 19 May, 2011 40 commits
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Benjamin Herrenschmidt authored
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Benjamin Herrenschmidt authored
Signed-off-by:Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Ira Snyder authored
This adds support for programming the data processing FPGAs on the OVRO CARMA board. These FPGAs have a special programming sequence that requires that we program the Freescale DMA engine, which is only available inside the kernel. Signed-off-by:
Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by:
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Ira Snyder authored
This driver allows userspace to access the data processing FPGAs on the OVRO CARMA board. It has two modes of operation: 1) random access This allows users to poke any DATA-FPGA registers by using mmap to map the address region directly into their memory map. 2) correlation dumping When correlating, the DATA-FPGA's have special requirements for getting the data out of their memory before the next correlation. This nominally happens at 64Hz (every 15.625ms). If the data is not dumped before the next correlation, data is lost. The data dumping driver handles buffering up to 1 second worth of correlation data from the FPGAs. This lowers the realtime scheduling requirements for the userspace process reading the device. Signed-off-by:
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Milton Miller authored
When creating an irq, don't allow a concurent driver request until we have caled map, which will likley call set_chip_and_handler to change the irq_chip and its operations. Similarly, when tearing down an IRQ, make sure no new uses come along while we change the irq back to the nop chip and then reset the descriptor to freed status. Signed-off-by:
Milton Miller <miltonm@bga.com> Signed-off-by:
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Milton Miller authored
The only references to the irq_map[].host field are internal to arch/powerpc/kernel/irq.c Signed-off-by:
Grant Likely <grant.likely@secretlab.ca> Signed-off-by:
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Milton Miller authored
Some irq_host implementations are using virq_to_host to check if they are the irq_host for a virtual irq. To allow us to make space versus time tradeoffs, replace this usage with an assertive virq_is_host that confirms or denies the irq is associated with the given irq_host. Signed-off-by:
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Milton Miller authored
Instead of checking for rogue msi numbers via the irq_map host field set the chip_data to h.host_data (which is the msic struct pointer) at map and compare it in get_irq. Signed-off-by:
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Milton Miller authored
Building on Grant's efforts to remove the irq_map array, this patch moves spider-pics use of virq_to_host() to use irq_data_get_chip_data and sets the irq chip data in the map call, like most other interrupt controllers in powerpc. Signed-off-by:
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Milton Miller authored
It was called from irq_create_mapping if that was called for a host and hwirq that was previously mapped, "to update the flags". But the only implementation was in beat_interrupt and all it did was repeat a hypervisor call without error checking that was performed with error checking at the beginning of the map hook. In addition, the comment on the beat remap hook says it will only called once for a given mapping, which would apply to map not remap. All flags should be known by the time the match hook is called, before we call the map hook. Removing this mostly unused hook will simpify the requirements of irq_domain concept. Signed-off-by:
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Milton Miller authored
Create a dummy irq_host using the generic dummy irq chip for the secondary cpus to use. Create a direct irq mapping for the ipi and register the ipi action handler against it. If for some unlikely reason part of this fails then don't detect the secondary cpus. This removes another instance of NO_IRQ_IGNORE, records the ipi stats for the secondary cpus, and runs the ipi on the interrupt stack. Signed-off-by:
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Milton Miller authored
If none of irq category bits were set mpc52xx_get_irq() would pass NO_IRQ_IGNORE (-1) to irq_linear_revmap, which does an unsigned compare and declares the interrupt above the linear map range. It then punts to irq_find_mapping, which performs a linear search of all irqs, which will likely miss and only then return NO_IRQ. If no status bit is set, then we should return NO_IRQ directly. The interrupt should not be suppressed from spurious counting, in fact that is the definition of supurious. Signed-off-by:
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Milton Miller authored
As NO_IRQ_IGNORE is only used between the static function cpld_pic_get_irq and its caller cpld_pic_cascade, and cpld_pic_cascade only uses it to suppress calling handle_generic_irq, we can change these uses to NO_IRQ and remove the extra tests and pathlength in cpld_pic_cascade. Signed-off-by:
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Milton Miller authored
handler_data should be reserved for flow handlers on the dependent irq, not consumed by the parent irq code that is part of the irq_chip code. The msi_data pointer was already set in msidesc->irqhost->hostdata and being copied to irq_data->chipdata in the msidesc->irqhost->map() method called via create_irq_mapping, so we can obtain the pointer from there and free the instance it in teardown_msi_irqs. Also remove the unnecessary cast of irq_get_handler_data in the cascade handler, which is the demux flow handler of the parent msi interrupt. (This is the expected usage for handler_data). Signed-off-by:
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Milton Miller authored
The msi platform device driver was abusing dev.platform_data for its platform_driver_data. Use the correct pointer for storage. Platform_data is supposed to be for platforms to communicate to drivers parameters that are not otherwise discoverable. Its lifetime matches the platform_device not the platform device driver. It is generally not needed for drivers that only support systems with device trees. Signed-off-by:
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Milton Miller authored
It was never called because the host is always IRQ_HOST_MAP_LEGACY. And what it purported to do was mask the interrupt (which will already have happend if we shutdown the interrupt), then synchronise_irq and clear the chip pointer, both of which will have been be done by the caller were we to call unmap on a legacy irq. Signed-off-by:
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Milton Miller authored
These all just clear chip or chipdata fields, which will be done by the generic code when we call irq_free_descs. Signed-off-by:
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Milton Miller authored
If for some reason the code incrorectly calls the wrong function to manage the revmap, not only should we warn, we should take action. However, in the paths we expect to be taken every delivered interrupt change to WARN_ON_ONCE. Use the if (WARN_ON(x)) format to get the unlikely for free. Signed-off-by:
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Milton Miller authored
Since the generic irq code uses a radix tree for sparse interrupts, the initcall ordering has been changed to initialize radix trees before irqs. We no longer need to defer creating revmap radix trees to the arch_initcall irq_late_init. Also, the kmem caches are allocated so we don't need to use zalloc_maybe_bootmem. Signed-off-by:
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Milton Miller authored
Since we already have a special case in map to set the ipi handler, use the desired flow. If we don't find an ics to handle the interrupt complain instead of returning 0 without having set a chip or handler. Signed-off-by:
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Milton Miller authored
Since there are only 4 messages, we can replace the atomic bit set (which uses atomic load reserve and store conditional sequence) with a byte stores to seperate bytes. We still have to perform a load reserve and store conditional sequence to avoid loosing messages on reception but we can do that with a single call to xchg. The do {} while and __BIG_ENDIAN specific mask testing was chosen by looking at the generated asm code. On gcc-4.4, the bit masking becomes a simple bit mask and test of the register returned from xchg without storing and loading the value to the stack like attempts with a union of bytes and an int (or worse, loading single bit constants from the constant pool into non-voliatle registers that had to be preseved on the stack). The do {} while avoids an unconditional branch to the end of the loop to test the entry / repeat condition of a while loop and instead optimises for the expected single iteration of the loop. We have a full mb() at the beginning to cover ordering between send, ipi, and receive so we can use xchg_local and forgo the further acquire and release barriers of xchg. Signed-off-by: -
Milton Miller authored
Compile the new smp ipi mux and demux code only if a platform will make use of it. The new config is selected as required. The new cause_ipi smp op is only available conditionally to point out configs where the select is required; this makes setting the op an immediate fail instead of a deferred unresolved symbol at link. This also creates a new config for power surge powermac upgrade support that can be disabled in expert mode but is default on. I also removed the depends / default y on CONFIG_XICS since it is selected by PSERIES. Signed-off-by:
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Milton Miller authored
Consolidate the mux and demux of ipi messages into smp.c and call a new smp_ops callback to actually trigger the ipi. The powerpc architecture code is optimised for having 4 distinct ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi single, scheduler ipi, and enter debugger). However, several interrupt controllers only provide a single software triggered interrupt that can be delivered to each cpu. To resolve this limitation, each smp_ops implementation created a per-cpu variable that is manipulated with atomic bitops. Since these lines will be contended they are optimialy marked as shared_aligned and take a full cache line for each cpu. Distro kernels may have 2 or 3 of these in their config, each taking per-cpu space even though at most one will be in use. This consolidation removes smp_message_recv and replaces the single call actions cases with direct calls from the common message recognition loop. The complicated debugger ipi case with its muxed crash handling code is moved to debug_ipi_action which is now called from the demux code (instead of the multi-message action calling smp_message_recv). I put a call to reschedule_action to increase the likelyhood of correctly merging the anticipated scheduler_ipi() hook coming from the scheduler tree; that single required call can be inlined later. The actual message decode is a copy of the old pseries xics code with its memory barriers and cache line spacing, augmented with a per-cpu unsigned long based on the book-e doorbell code. The optional data is set via a callback from the implementation and is passed to the new cause-ipi hook along with the logical cpu number. While currently only the doorbell implemntation uses this data it should be almost zero cost to retrieve and pass it -- it adds a single register load for the argument from the same cache line to which we just completed a store and the register is dead on return from the call. I extended the data element from unsigned int to unsigned long in case some other code wanted to associate a pointer. The doorbell check_self is replaced by a call to smp_muxed_ipi_resend, conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed to CONFIG_SMP but I left it with BOOKE for now. Also, the doorbell interrupt vector for book-e was not calling irq_enter and irq_exit, which throws off cpu accounting and causes code to not realize it is running in interrupt context. Add the missing calls. Signed-off-by:
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Milton Miller authored
I can't see any reason these functions are needed by machdep.h and they are all hidden by CONFIG_SMP with no UP alternative. Also move the declarations for the fallback timebase ops, which are used to fill in the smp ops. Signed-off-by:
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Milton Miller authored
I have no idea if the beat hypervisor supports multiple cpus in a partition, but the code has not been touched since these stubs were added in February of 2007 except to move them in April of 2008. These are stubs: start_cpu always returns fail (which is dropped), the message passing and reciving are empty functions, and the top of file comment says "Incomplete". Signed-off-by:
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Milton Miller authored
Replace all remaining callers of alloc_maybe_bootmem with zalloc_maybe_bootmem. The callsite in pci_dn is followed with a memset to clear the memory, and not zeroing at the other callsites in the celleb fake pci code could lead to following uninitialized memory as pointers or even freeing said pointers on error paths. Signed-off-by:
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Milton Miller authored
Its unused, and of the three declarations, one is duplicated in pmac.h, the second is static and the third is renamed and static. Signed-off-by:
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Milton Miller authored
Now that MSG_ALL and MSG_ALL_BUT_SELF have been eliminated, smp_mpic_mesage_pass no longer needs to lookup the cpumask just to have mpic_send_ipi extract part of it and recode it in a NR_CPUS loop by mpic_physmask. Signed-off-by:
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Milton Miller authored
Now that smp_ops->smp_message_pass is always called with an (online) cpu number for the target remove the checks for MSG_ALL and MSG_ALL_BUT_SELF. Signed-off-by:
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Milton Miller authored
The only user of MSG_ALL_BUT_SELF in the whole kernel tree is powerpc, and it only uses it to start the debugger. Both debuggers always call smp_send_debugger_break with MSG_ALL_BUT_SELF, and only mpic can do anything more optimal than a loop over all online cpus, but all message passing implementations have to code for this special delivery target. Convert smp_send_debugger_break to take void and loop calling the smp_ops message_pass function for each of the other cpus in the online cpumask. Use raw_smp_processor_id() because we are either entering the debugger or trying to start kdump and the additional warning it not useful were it to trigger. Signed-off-by:
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Milton Miller authored
mpic_set_affinity is allocating and freeing a cpumask var even though it was breaking the cpumask abstraction when passing the mask to mpic_physmask. It also didn't have any check for allocatin failure. Break the cpumask abstraction earlier and use simple bitwise and of the bits from the mask with the bits of cpu_online_mask. Signed-off-by:
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Milton Miller authored
mpic_physmask was looping NR_CPUS times over a mask that was passed as a u32. Since mpic is architecturaly limited to 32 physical cpus, clamp the logical cpus to 32 when compiling (we could also clamp at runtime to nr_cpu_ids). Signed-off-by:
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Milton Miller authored
c1854e00 (powerpc: Set nr_cpu_ids early and use it to free PACAs) copied the formerly static setup_nr_cpu_ids from init/main.c but 34db18a0 (smp: move smp setup functions to kernel/smp.c) moved it to kernel/smp.c with a declaration in include/linux/smp.h, so we can call it instead of replicating it. Signed-off-by:
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Milton Miller authored
Now that we never set a cpu above nr_cpu_ids possible we can limit our initial paca allocation to nr_cpu_ids. We can then clamp the number of cpus in platforms/iseries/setup.c. Signed-off-by:
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Milton Miller authored
We should not set cpus above nr_cpu_ids to possible. While we will trigger a warning with CONFIG_CPUMASK_DEBUG, even then the mask initializers will set the bits beyond what the iterators check and cause nr_cpu_ids to increase. Respecting nr_cpu_ids during setup will allow us to use it in our initial paca allocation. It can be reduced from NR_CPUS by the existing early param nr_cpus=, which was added in 2b633e3f (smp: Use nr_cpus= to set nr_cpu_ids early). We already call parse_early_parms between finding the command line and allocating the pacas. Signed-off-by:
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Milton Miller authored
9cb82f2f (Make iSeries spin on __secondary_hold_spinloop, like pSeries) added a load of current_set but this load was repeated later and we don't even have the paca yet. It also checked __secondary_hold_spinloop with a 32 bit compare instead of a 64 bit compare. b6f6b98a (Don't spin on sync instruction at boot time) missed the copy of the startup code in iseries. 1426d5a3 (Dynamically allocate pacas) doesn't allow for pacas to be less than lppacas and recalculated the paca location from the cpu id in r0 every time through the secondary loop. Various revisions over time made the comments on conditional branches confusing with respect to being a hold loop or forward progress Mostly in-order description of the changes: Replicate the few lines of code saved by the ugly scoped ifdef CONFIG_SMP in the secondary loop between yielding on UP and marking time with the hypervisor on SMP. Always compile the iseries_secondary_yield loop and use it if the cpu id is above nr_cpu_ids. Change all forward progress paths to be forward branches to the next numerical label. Assign a label to all loops. Move all sync instructions from the loops to the forward progress path. Wait to load current_set until paca is set to go. Move the iseries_secondary_smp_loop label to cover the whole spin loop. Add HMT_MEDIUM when we make forward progress. Signed-off-by:
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Milton Miller authored
Starting with 1426d5a3 (powerpc: Dynamically allocate pacas) the space for pacas beyond cpu_possible is freed, but we failed to update the loop in crash.c. Since c1854e00 (powerpc: Set nr_cpu_ids early and use it to free PACAs) the number of pacas allocated is always nr_cpu_ids. Signed-off-by:
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Milton Miller authored
Starting with 1426d5a3 (powerpc: Dynamically allocate pacas) we free the memory for pacas beyond cpu_possible, but we failed to update the loop the secondary cpus use to find their paca. If the system has running cpu threads for which the kernel did not allocate a paca for they will search the memory that was freed. For instance this could happen when the device tree for a kdump kernel was not updated after a cpu hotplug, or the kernel is running with more cpus than the kernel was configured. Since c1854e00 (powerpc: Set nr_cpu_ids early and use it to free PACAs) we set nr_cpu_ids before telling the cpus to advance, so use that to limit the search. We can't reference nr_cpu_ids without CONFIG_SMP because it is defined as 1 instead of a memory location, but any extra threads should be sent to kexec_wait in that case anyways, so make that explicit and remove the search loop for UP. Note to stable: The fix also requires c1854e00 (powerpc: Set nr_cpu_ids early and use it to free PACAs) to function. Also 9d07bc84 (Properly handshake CPUs going out of boot spin loop) affects the second chunk, specifically the branch target was 3b before and is 4b after that patch, and there was a blank line before the #ifdef CONFIG_SMP that was removed Cc: <stable@kernel.org> # .34.x: c1854e00 powerpc: Set nr_cpu_ids early Cc: <stable@kernel.org> # .34.x Signed-off-by:
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Milton Miller authored
Commit 1fc711f7 (powerpc/kexec: Fix race in kexec shutdown) moved the write to signal the cpu had exited the kernel from before the transition to real mode in kexec_smp_wait to kexec_wait. Unfornately it missed that kexec_wait is used both by cpus leaving the kernel and by secondary slave cpus that were not allocated a paca for what ever reason -- they could be beyond nr_cpus or not described in the current device tree for whatever reason (for example, kexec-load was not refreshed after a cpu hotplug operation). Cpus coming through that path they will write to paca[NR_CPUS] which is beyond the space allocated for the paca data and overwrite memory not allocated to pacas but very likely still real mode accessable). Move the write back to kexec_smp_wait, which is used only by cpus that found their paca, but after the transition to real mode. Signed-off-by:
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Anton Blanchard authored
I have a report of an FWNMI with an r3 value that we think is corrupt, but since we don't print r3 we have no idea what was wrong with it. Signed-off-by:
Anton Blanchard <anton@samba.org> Signed-off-by:
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