linux/arch/powerpc/kernel
Benjamin Herrenschmidt 7191b61575 powerpc/pmac: Early debug output on screen on 64-bit macs
We have a bunch of CONFIG_PPC_EARLY_DEBUG_* options that are intended
for bringup/debug only. They hard wire a machine specific udbg backend
very early on (before we even probe the platform), and use whatever
tricks are available on each machine/cpu to be able to get some kind
of output out there early on.

So far, on powermac with no serial ports, we have CONFIG_PPC_EARLY_DEBUG_BOOTX
to use the low-level btext engine on the screen, but it doesn't do much, at
least on 64-bit. It only really gets enabled after the platform has been
probed and the MMU enabled.

This adds a way to enable it much earlier. From prom_init.c (while still
running with Open Firmware), we grab the screen details and set things up
using the physical address of the frame buffer.

Then btext itself uses the "rm_ci" feature of the 970 processor (Real
Mode Cache Inhibited) to access it while in real mode.

We need to do a little bit of reorg of the btext code to inline things
better, in order to limit how much we touch memory while in this mode as
the consequences might be ... interesting.

This successfully allowed me to debug problems early on with the G5
(related to gold being broken vs. ppc64 kernels).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-08-14 14:57:40 +10:00
..
vdso32 powerpc: Add VDSO version of time 2013-04-23 16:05:05 +10:00
vdso64 powerpc: Add VDSO version of time 2013-04-23 16:05:05 +10:00
.gitignore
align.c powerpc: Handle unaligned ldbrx/stdbrx 2013-08-14 11:50:20 +10:00
asm-offsets.c powerpc/perf: Drop MMCRA from thread_struct 2013-07-01 11:50:07 +10:00
audit.c
btext.c powerpc/pmac: Early debug output on screen on 64-bit macs 2013-08-14 14:57:40 +10:00
cacheinfo.c powerpc: Delete __cpuinit usage from all users 2013-07-01 11:10:36 +10:00
cacheinfo.h
clock.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
compat_audit.c
cpu_setup_6xx.S
cpu_setup_44x.S
cpu_setup_a2.S powerpc: Enforce usage of RA 0-R31 where possible 2012-07-10 19:18:35 +10:00
cpu_setup_fsl_booke.S powerpc/85xx: Add machine check handler to fix PCIe erratum on mpc85xx 2013-07-30 15:50:07 -05:00
cpu_setup_pa6t.S
cpu_setup_power.S powerpc: Fix TLB cleanup at boot on POWER8 2013-05-24 18:13:44 +10:00
cpu_setup_ppc970.S powerpc, KVM: Split HVMODE_206 cpu feature bit into separate HV and architecture bits 2011-07-12 13:16:58 +03:00
cputable.c Merge remote-tracking branch 'scott/next' into next 2013-08-09 16:01:40 +10:00
crash_dump.c powerpc: Remove savemaxmem parameter setup 2013-07-03 16:08:03 -07:00
crash.c Disintegrate asm/system.h for PowerPC 2012-03-28 18:30:02 +01:00
dbell.c powerpc: Add accounting for Doorbell interrupts 2013-04-18 15:59:55 +10:00
dma-iommu.c powerpc/dma-iommu: Fix IOMMU window check 2012-08-24 20:26:07 +10:00
dma-swiotlb.c powerpc/swiotlb: Enable at early stage and disable if not necessary 2012-09-12 14:57:09 -05:00
dma.c powerpc/kernel: Remove uses of abs_to_virt() and virt_to_abs() 2012-09-05 15:19:30 +10:00
eeh_cache.c powerpc/eeh: Remove reference to PCI device 2013-07-24 14:18:46 +10:00
eeh_dev.c powerpc/eeh: Move common part to kernel directory 2013-06-20 17:05:35 +10:00
eeh_driver.c powerpc/eeh: Fix unbalanced enable for IRQ 2013-07-24 14:18:49 +10:00
eeh_event.c powerpc/eeh: Use interruptible sleep in keehd 2013-06-25 17:24:41 +10:00
eeh_pe.c powerpc/eeh: Don't use pci_dev during BAR restore 2013-07-24 14:18:49 +10:00
eeh_sysfs.c powerpc/eeh: Introdce flag to protect sysfs 2013-07-24 14:18:49 +10:00
eeh.c powerpc/eeh: Introdce flag to protect sysfs 2013-07-24 14:18:49 +10:00
entry_32.S powerpc/32bit:Store temporary result in r0 instead of r8 2013-06-01 08:29:27 +10:00
entry_64.S powerpc: Restore dbcr0 on user space exit 2013-06-20 17:04:19 +10:00
epapr_hcalls.S powerpc: Add paravirt idle loop for 64-bit Book-E 2013-03-13 14:19:36 -05:00
epapr_paravirt.c powerpc/85xx: Move ePAPR paravirt initialization earlier 2013-08-07 18:38:06 -05:00
exceptions-64e.S powerpc/booke64: Fix kernel hangs at kernel_dbg_exc 2013-05-14 16:00:19 +10:00
exceptions-64s.S Linux 3.10 2013-07-01 17:57:25 +10:00
fadump.c mm/ppc: use common help functions to free reserved pages 2013-04-29 15:54:30 -07:00
firmware.c powerpc: fix implicit use of cache.h in kernel/firmware.c 2011-10-31 19:30:41 -04:00
fpu.S powerpc: Add FP/VSX and VMX register load functions for transactional memory 2013-02-15 16:58:52 +11:00
fsl_booke_entry_mapping.S
ftrace.c powerpc/ftrace: Trace function graph entry before updating index 2012-07-27 11:42:34 +10:00
head_8xx.S powerpc: Call do_page_fault() with interrupts off 2012-03-09 10:55:08 +11:00
head_32.S powerpc: Call do_page_fault() with interrupts off 2012-03-09 10:55:08 +11:00
head_40x.S powerpc: Enable the Watchdog vector for 405 2013-01-10 14:43:46 +11:00
head_44x.S powerpc: Fix interrupt range check on debug exception 2013-05-02 10:31:01 +10:00
head_64.S powerpc: Align p_toc 2013-08-14 11:50:19 +10:00
head_booke.h powerpc: Fix interrupt range check on debug exception 2013-05-02 10:31:01 +10:00
head_fsl_booke.S powerpc: Fix interrupt range check on debug exception 2013-05-02 10:31:01 +10:00
hw_breakpoint.c powerpc/hw_brk: Fix off by one error when validating DAWR region end 2013-07-02 08:20:49 +10:00
ibmebus.c ibmebus: convert of_platform_driver to platform_driver 2013-06-12 12:37:26 +01:00
idle_6xx.S powerpc: Use CURRENT_THREAD_INFO instead of open coded assembly 2012-07-11 14:18:22 +10:00
idle_book3e.S powerpc: Add paravirt idle loop for 64-bit Book-E 2013-03-13 14:19:36 -05:00
idle_e500.S powerpc: Use CURRENT_THREAD_INFO instead of open coded assembly 2012-07-11 14:18:22 +10:00
idle_power4.S powerpc: Use CURRENT_THREAD_INFO instead of open coded assembly 2012-07-11 14:18:22 +10:00
idle_power7.S powerpc/powernv: Always go into nap mode when CPU is offline 2012-09-05 16:05:20 +10:00
idle.c powerpc/idle: Convert use of typedef ctl_table to struct ctl_table 2013-07-01 11:10:35 +10:00
io-workarounds.c powerpc: Replace find_linux_pte with find_linux_pte_or_hugepte 2013-06-21 16:01:54 +10:00
io.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
iomap.c powerpc: switch to GENERIC_PCI_IOMAP 2011-11-28 21:13:18 +02:00
iommu.c powerpc/vfio: Enable on PowerNV platform 2013-06-20 16:55:14 +10:00
irq.c powerpc: Rename PMU interrupts from CNT to PMI 2013-08-01 13:11:46 +10:00
isa-bridge.c POWERPC: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
jump_label.c powerpc: Fix build breakage in jump_label.c 2011-11-16 14:25:19 +11:00
kgdb.c powerpc/kgdb: Removed kmalloc returned value cast 2013-04-18 13:03:56 +10:00
kprobes.c powerpc: Move the single step enable code to a generic path 2013-06-20 16:55:09 +10:00
kvm_emul.S KVM: PPC: Not optimizing MSR_CE and MSR_ME with paravirt. 2012-05-30 11:43:11 +02:00
kvm.c mm: enhance free_reserved_area() to support poisoning memory with zero 2013-07-03 16:07:32 -07:00
l2cr_6xx.S Fix common misspellings 2011-03-31 11:26:23 -03:00
legacy_serial.c powerpc: Fix a number of sparse warnings 2013-08-14 11:50:24 +10:00
lparcfg.c powerpc: Stop using non-architected shared_proc field in lppaca 2013-08-14 11:50:26 +10:00
machine_kexec_32.c treewide: convert uses of ATTRIB_NORETURN to __noreturn 2012-01-12 20:13:03 -08:00
machine_kexec_64.c powerpc/kexec: Fix kexec when using VMX optimised memcpy 2013-05-14 14:36:23 +10:00
machine_kexec.c powerpc+of: Rename the drivers/of prom_* functions to of_* 2012-11-15 12:56:52 +11:00
Makefile powerpc/eeh: Move common part to kernel directory 2013-06-20 17:05:35 +10:00
misc_32.S powerpc: Remove the symbol __flush_icache_range 2013-08-14 14:56:44 +10:00
misc_64.S powerpc/pmac: Early debug output on screen on 64-bit macs 2013-08-14 14:57:40 +10:00
misc.S powerpc: switch to generic sys_execve()/kernel_execve() 2012-09-30 23:35:51 -04:00
module_32.c powerpc: Fix kernel panic during kernel module load 2012-06-08 19:59:08 +10:00
module_64.c powerpc: Build kernel with -mcmodel=medium 2013-01-10 17:00:31 +11:00
module.c powerpc: remove non-required uses of include <linux/module.h> 2011-10-31 19:30:44 -04:00
msi.c
nvram_64.c powerpc/nvram64: Need return the related error code on failure occurs 2013-07-01 11:46:56 +10:00
of_platform.c powerpc/eeh: Fix crash when adding a device in a slot with DDW 2013-01-10 17:01:58 +11:00
paca.c powerpc: Move boot_paca into early_setup 2013-02-15 16:54:48 +11:00
pci_32.c powerpc/pci: Support per-aperture memory offset 2013-05-06 13:40:40 +10:00
pci_64.c powerpc/pci: Don't use bitfield for force_32bit_msi 2013-08-14 11:50:25 +10:00
pci_dn.c powerpc: Make radeon 32-bit MSI quirk work on powernv 2013-05-24 18:13:45 +10:00
pci_of_scan.c powerpc/pci: Partial tree hotplug support 2013-07-24 14:18:48 +10:00
pci-common.c powerpc/pci: Remove duplicate check in pcibios_fixup_bus() 2013-08-14 14:57:36 +10:00
pci-hotplug.c powerpc/pci: Partial tree hotplug support 2013-07-24 14:18:48 +10:00
pmc.c bug.h: add include of it to various implicit C users 2012-02-29 17:15:08 -05:00
ppc32.h powerpc: switch to generic old sigaction() 2013-02-03 18:16:10 -05:00
ppc_ksyms.c powerpc: Remove the symbol __flush_icache_range 2013-08-14 14:56:44 +10:00
ppc_save_regs.S Fix common misspellings 2011-03-31 11:26:23 -03:00
proc_powerpc.c proc_powerpc: switch to fixed_size_llseek() 2013-06-29 12:57:50 +04:00
process.c Linux 3.10 2013-07-01 17:57:25 +10:00
prom_init_check.sh powerpc/pmac: Early debug output on screen on 64-bit macs 2013-08-14 14:57:40 +10:00
prom_init.c powerpc/pmac: Early debug output on screen on 64-bit macs 2013-08-14 14:57:40 +10:00
prom_parse.c powerpc: remove non-required uses of include <linux/module.h> 2011-10-31 19:30:44 -04:00
prom.c powerpc: Handle both new style and old style reserve maps 2013-07-02 08:20:49 +10:00
ptrace32.c powerpc: fixing ptrace_get_reg to return an error 2013-04-18 13:03:57 +10:00
ptrace.c ptrace/powerpc: revert "hw_breakpoints: Fix racy access to ptrace breakpoints" 2013-07-09 10:33:25 -07:00
reloc_32.S powerpc: Don't flush/invalidate the d/icache for an unknown relocation type 2013-07-01 11:10:34 +10:00
reloc_64.S
rtas_flash.c powerpc/rtas_flash: Fix validate_flash buffer overflow issue 2013-05-14 14:36:26 +10:00
rtas_pci.c powerpc/kernel: Cleanup on rtas_pci.c 2013-04-18 13:03:48 +10:00
rtas-proc.c
rtas-rtc.c powerpc/rtas-rtc: remove sideeffects of printk_ratelimit 2011-06-29 15:30:43 +10:00
rtas.c powerpc: Delete __cpuinit usage from all users 2013-07-01 11:10:36 +10:00
rtasd.c powerpc/pseries: Add /proc interface to control topology updates 2013-04-26 16:08:26 +10:00
setup_32.c powerpc/85xx: Move ePAPR paravirt initialization earlier 2013-08-07 18:38:06 -05:00
setup_64.c powerpc/pmac: Early debug output on screen on 64-bit macs 2013-08-14 14:57:40 +10:00
setup-common.c powerpc: remove PReP platform 2013-04-18 13:03:53 +10:00
setup.h
signal_32.c powerpc: Fix VRSAVE handling 2013-08-14 14:57:18 +10:00
signal_64.c powerpc: Fix VRSAVE handling 2013-08-14 14:57:18 +10:00
signal.c powerpc/tm: Fix userspace stack corruption on signal delivery for active transactions 2013-06-01 08:29:23 +10:00
signal.h powerpc/tm: Fix userspace stack corruption on signal delivery for active transactions 2013-06-01 08:29:23 +10:00
smp-tbsync.c POWERPC: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
smp.c powerpc: Add smp_generic_cpu_bootable 2013-08-14 14:56:50 +10:00
softemu8xx.c Disintegrate asm/system.h for PowerPC 2012-03-28 18:30:02 +01:00
stacktrace.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
suspend.c
swsusp_32.S Fix common misspellings 2011-03-31 11:26:23 -03:00
swsusp_64.c Disintegrate asm/system.h for PowerPC 2012-03-28 18:30:02 +01:00
swsusp_asm64.S
swsusp_booke.S powerpc/mpc85xx: invalidate TLB after hibernation resume 2013-07-30 15:50:08 -05:00
swsusp.c Disintegrate asm/system.h for PowerPC 2012-03-28 18:30:02 +01:00
sys_ppc32.c unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE 2013-05-09 13:46:38 -04:00
syscalls.c powerpc: Fix personality handling in ppc64_personality() 2012-08-24 20:26:07 +10:00
sysfs.c powerpc: Delete __cpuinit usage from all users 2013-07-01 11:10:36 +10:00
systbl_chk.c
systbl_chk.sh
systbl.S
tau_6xx.c
time.c powerpc: Delete __cpuinit usage from all users 2013-07-01 11:10:36 +10:00
tm.S powerpc: Fix VRSAVE handling 2013-08-14 14:57:18 +10:00
traps.c powerpc/85xx: Add machine check handler to fix PCIe erratum on mpc85xx 2013-07-30 15:50:07 -05:00
udbg_16550.c powerpc: Add early debug for WSP platforms 2011-05-06 13:32:41 +10:00
udbg.c powerpc: Add a configuration option for early BootX/OpenFirmware debug 2013-06-20 16:55:12 +10:00
uprobes.c uretprobes/powerpc: Hijack return address 2013-04-13 15:31:56 +02:00
vdso.c powerpc: Delete __cpuinit usage from all users 2013-07-01 11:10:36 +10:00
vecemu.c
vector.S powerpc: Add FP/VSX and VMX register load functions for transactional memory 2013-02-15 16:58:52 +11:00
vio.c POWERPC: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
vmlinux.lds.S powerpc/modules: Module CRC relocation fix causes perf issues 2013-07-24 14:18:43 +10:00