From: Vijaya Kumar K <Vijaya.Kumar(a)caviumnetworks.com>
Based on the step-handler and break-handler hooks patch from
Sandeepa, KGDB debugging support is added for EL1
debug in AArch64 mode.
In first patch, PSTATE.D is set correctly
In second patch,register layout is updated to be inline with GDB tool.
Basic GDB connection, break point set/clear and info commands
are supported except step/next debugging
With second patch, step/next debugging support is added, where in
pc is updated to point to the instruction to be stepped and
stopped.
With third patch, the compile time breakpoint instruction
reordering is fixed by making kgbd_breakpoint() as noinline
Tested with ARM64 simulator
v9:
- minor code movement comments fix
v8:
- fixed comments on local_dbg_{save,restore} macros
- instruction_pointer() macro to return unsigned long to fix
compilation warnings
v7:
- Changes made to set PSTATE.D properly
- Performed KGDB boot tests
- Fixed compilation warnings in driver/misc/kgbdts.c
Results:
kgdb boot test:
[32927.237895] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[32927.266066] kgdb: Registered I/O driver kgdbts.
[32927.266419] kgdb: Waiting for connection from remote gdb...
[32927.268598] kgdbts:RUN plant and detach test
[32927.270683] kgdbts:RUN sw breakpoint test
[32927.287659] kgdbts:RUN bad memory access test
[32927.290322] kgdbts:RUN singlestep test 1000 iterations
[32927.330342] kgdbts:RUN singlestep [0/1000]
[32931.286356] kgdbts:RUN singlestep [100/1000]
[32935.242536] kgdbts:RUN singlestep [200/1000]
[32939.205392] kgdbts:RUN singlestep [300/1000]
[32943.169522] kgdbts:RUN singlestep [400/1000]
[32947.231868] kgdbts:RUN singlestep [500/1000]
[32951.188008] kgdbts:RUN singlestep [600/1000]
[32955.332243] kgdbts:RUN singlestep [700/1000]
[32959.467109] kgdbts:RUN singlestep [800/1000]
[32963.430888] kgdbts:RUN singlestep [900/1000]
[32967.346992] kgdbts:RUN do_fork for 100 breakpoints
kgdb test from sysfs:
~ # echo V1F1000 > /sys/module/kgdbts/parameters/kgdbts
[33231.554237] kgdb: Registered I/O driver kgdbts.
[33231.554677] kgdbts:RUN plant and detach test
[33231.557072] kgdbts:RUN sw breakpoint test
[33231.576980] kgdbts:RUN bad memory access test
[33231.580022] kgdbts:RUN singlestep test 1000 iterations
[33231.627056] kgdbts:RUN singlestep [0/1000]
[33235.954027] kgdbts:RUN singlestep [100/1000]
[33240.429086] kgdbts:RUN singlestep [200/1000]
[33244.687118] kgdbts:RUN singlestep [300/1000]
[33248.945191] kgdbts:RUN singlestep [400/1000]
[33253.203751] kgdbts:RUN singlestep [500/1000]
[33257.462019] kgdbts:RUN singlestep [600/1000]
[33261.817809] kgdbts:RUN singlestep [700/1000]
[33266.081268] kgdbts:RUN singlestep [800/1000]
[33270.339813] kgdbts:RUN singlestep [900/1000]
[33274.712404] kgdbts:RUN do_fork for 1000 breakpoints
~ #
v6:
- Change pstate register to 8 bytes to make endian nuetral.
Use GDB below GDB patch to display pstate in Big endian mode.
https://sourceware.org/ml/gdb-patches/2013-12/msg00720.html
Thanks to Andrew.
v5:
- Updated BRK #imm16 value to 0x400 & 0x401 as per recommendation
as per Marcus recommendataion
http://patchwork.ozlabs.org/patch/290801/
- Rebased to 3.13 AArch64 kernel
v4:
- Updated kgdb_single_step and kgdb_cpu_doing_single_step
variables properly based on gdb state
v3:
- Rebased to v4 version of Sandeepa Prabhu's patch (patch 1)
- Made dynamic break point instruction encoding generic
- Made ESR value encoding generic for dynamic and compile break point
- Used memcpy and memset to copy register contents to gdb buffer
- Fixed reordering of break point instruction by compiler with
patch 3
- Rebased against AAach64 upstream kernel
v2:
- Moved break instruction encoding to debug-monitors.h file
- Fixed endianess of compile break instruction encoding
- Updated I/O buffer sizes
- Updated register buffer size
- Remove changes to debug_exception handler in entry.S for
- ELR update and step debugging with update pc instead of ELR
- Rebased against AArch64 upstream kernel
v1:
- Initial patch-set
Vijaya Kumar K (6):
arm64: Add macros to manage processor debug state
arm64: KGDB: Add Basic KGDB support
arm64: KGDB: Add step debugging support
KGDB: make kgdb_breakpoint() as noinline
misc: debug: remove compilation warnings
arm64: KGDB: Add KGDB config
arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/debug-monitors.h | 64 ++++--
arch/arm64/include/asm/irqflags.h | 23 +++
arch/arm64/include/asm/kgdb.h | 84 ++++++++
arch/arm64/include/asm/ptrace.h | 2 +-
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/debug-monitors.c | 1 +
arch/arm64/kernel/kgdb.c | 336 +++++++++++++++++++++++++++++++
kernel/debug/debug_core.c | 2 +-
9 files changed, 495 insertions(+), 19 deletions(-)
create mode 100644 arch/arm64/include/asm/kgdb.h
create mode 100644 arch/arm64/kernel/kgdb.c
--
1.7.9.5
Governors might use cpufreq_global_kobject when they don't have governor per
policy. And so they must initialize it with a call to
cpufreq_get_global_kobject(). Also after removing sysfs entries we must take the
refcount down as well with a call to: cpufreq_put_global_kobject().
If above isn't done we will see following boot crash:
kernel BUG at /home/arm/work/kernel/mywork/linux.git/fs/sysfs/group.c:92!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.0-rc1-00852-g293953e-dirty #171
task: ee094000 ti: ee092000 task.ti: ee092000
PC is at internal_create_group+0x1f0/0x224
LR is at cpufreq_governor_interactive+0x13c/0x504
pc : [<c01094a0>] lr : [<c02aff44>] psr: 60000113
sp : ee093c90 ip : 00013880 fp : ee301368
r10: ee301300 r9 : c05084f0 r8 : c0531814
r7 : 00000000 r6 : ee105640 r5 : ee301300 r4 : ee105640
r3 : c0531a88 r2 : c0531814 r1 : 00000000 r0 : 00000000
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 10c5387d Table: 4000406a DAC: 00000015
<snip>
[<c01094a0>] (internal_create_group) from [<c02aff44>] (cpufreq_governor_interactive+0x13c/0x504)
[<c02aff44>] (cpufreq_governor_interactive) from [<c02ab090>] (__cpufreq_governor+0x78/0x1f0)
[<c02ab090>] (__cpufreq_governor) from [<c02ac224>] (cpufreq_set_policy+0x144/0x1c8)
[<c02ac224>] (cpufreq_set_policy) from [<c02ac530>] (cpufreq_init_policy+0x54/0x80)
[<c02ac530>] (cpufreq_init_policy) from [<c02ad8b0>] (__cpufreq_add_dev.isra.27+0x72c/0x804)
[<c02ad8b0>] (__cpufreq_add_dev.isra.27) from [<c0223610>] (subsys_interface_register+0x80/0xc4)
[<c0223610>] (subsys_interface_register) from [<c02ac890>] (cpufreq_register_driver+0xb8/0x214)
[<c02ac890>] (cpufreq_register_driver) from [<c02b0744>] (exynos_cpufreq_probe+0xf4/0x1a0)
[<c02b0744>] (exynos_cpufreq_probe) from [<c0225808>] (platform_drv_probe+0x18/0x48)
[<c0225808>] (platform_drv_probe) from [<c0224498>] (driver_probe_device+0x100/0x218)
[<c0224498>] (driver_probe_device) from [<c022463c>] (__driver_attach+0x8c/0x90)
[<c022463c>] (__driver_attach) from [<c0222cb8>] (bus_for_each_dev+0x54/0x88)
[<c0222cb8>] (bus_for_each_dev) from [<c0223c78>] (bus_add_driver+0xd4/0x1d0)
[<c0223c78>] (bus_add_driver) from [<c0224c58>] (driver_register+0x78/0xf4)
[<c0224c58>] (driver_register) from [<c0008854>] (do_one_initcall+0xe4/0x140)
[<c0008854>] (do_one_initcall) from [<c04c8c68>] (kernel_init_freeable+0xfc/0x1c8)
[<c04c8c68>] (kernel_init_freeable) from [<c0379abc>] (kernel_init+0x8/0x118)
[<c0379abc>] (kernel_init) from [<c000e5f8>] (ret_from_fork+0x14/0x3c)
Code: ebfc504c eaffffe0 e3500000 1affff8e (e7f001f2)
---[ end trace 04d313d9fc559575 ]---
Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
Signed-off-by: Viresh Kumar <viresh.kumar(a)linaro.org>
---
Todd,
You need this patch for all kernels after 3.10. Not sure if android has already
hit 3.11 or not.. Though I haven't seena a branch for that :)
drivers/cpufreq/cpufreq_interactive.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c
index ff77b30..5286e57 100644
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -1157,6 +1157,9 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
if (!have_governor_per_policy())
common_tunables = tunables;
+ if (!have_governor_per_policy())
+ WARN_ON(cpufreq_get_global_kobject());
+
rc = sysfs_create_group(get_governor_parent_kobj(policy),
get_sysfs_attr());
if (rc) {
@@ -1185,6 +1188,10 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
sysfs_remove_group(get_governor_parent_kobj(policy),
get_sysfs_attr());
+
+ if (!have_governor_per_policy())
+ cpufreq_put_global_kobject();
+
kfree(tunables);
common_tunables = NULL;
}
--
1.7.12.rc2.18.g61b472e
Hi,
This patch adds support for PCI to AArch64. It is based on the patch posted
here [1] that adds support for creating generic host bridge structure from
device tree. With that in place, I was able to boot an FPGA platform that
has PCIe host bridge support and use a PCIe network card.
The API used is different from the one used by ARM architecture. There is
no pci_common_init_dev() function and no hw_pci structure, as that is no
longer needed. Once the last signature is added to the legal agreement, I
will post the host bridge driver code that I am using. Meanwhile, here
is an example of what the probe function looks like, posted as an example:
static int myhostbridge_probe(struct platform_device *pdev)
{
int err;
struct device_node *dev;
struct pci_host_bridge *bridge;
struct resource bus_range;
struct myhostbridge_port *pp;
LIST_HEAD(resources);
dev = pdev->dev.of_node;
if (!of_device_is_available(dev)) {
pr_warn("%s: disabled\n", dev->full_name);
return -ENODEV;
}
pp = kzalloc(sizeof(struct myhostbridge_port), GFP_KERNEL);
if (!pp)
return -ENOMEM;
err = of_pci_parse_bus_range(dev, &bus_range);
if (err) {
bus_range.start = 0;
bus_range.end = 255;
bus_range.flags = IORESOURCE_BUS;
}
pci_add_resource(&resources, &bus_range);
bridge = pci_host_bridge_of_init(&pdev->dev, 0, &myhostbridge_ops, pp, &resources);
if (!bridge) {
err = -EINVAL;
goto bridge_init_fail;
}
err = myhostbridge_setup(bridge->bus);
if (err)
goto bridge_init_fail;
/*
* Add flags here, this is just an example
*/
pci_add_flags(PCI_ENABLE_PROC_DOMAINS | PCI_COMPAT_DOMAIN_0);
pci_add_flags(PCI_REASSIGN_ALL_BUS | PCI_REASSIGN_ALL_RSRC);
bus_range.end = pci_scan_child_bus(bridge->bus);
pci_bus_update_busn_res_end(bridge->bus, bus_range.end);
pci_assign_unassigned_bus_resources(bridge->bus);
pci_bus_add_devices(bridge->bus);
return 0;
bridge_init_fail:
kfree(pp);
pci_free_resource_list(&resources);
return err;
}
Best regards,
Liviu
[1] http://marc.info/?l=linux-pci&m=139145254821334&w=2
Liviu Dudau (1):
arm64: Add support for PCI
arch/arm64/Kconfig | 17 +++++++
arch/arm64/include/asm/Kbuild | 1 +
arch/arm64/include/asm/io.h | 4 ++
arch/arm64/include/asm/pci.h | 35 +++++++++++++
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/pci.c | 112 ++++++++++++++++++++++++++++++++++++++++++
6 files changed, 170 insertions(+)
create mode 100644 arch/arm64/include/asm/pci.h
create mode 100644 arch/arm64/kernel/pci.c
--
1.8.5.3
