kernel.git/arch/powerpc/kernel/prom.c, branch linux-4.14.y

powerpc/64: Init jump labels before parse_early_param()

2022-08-25T09:11:37Z

[ Upstream commit ca829e05d3d4f728810cc5e4b468d9ebc7745eb3 ] On 64-bit, calling jump_label_init() in setup_feature_keys() is too late because static keys may be used in subroutines of parse_early_param() which is again subroutine of early_init_devtree(). For example booting with "threadirqs": static_key_enable_cpuslocked(): static key '0xc000000002953260' used before call to jump_label_init() WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xfc/0x120 ... NIP static_key_enable_cpuslocked+0xfc/0x120 LR static_key_enable_cpuslocked+0xf8/0x120 Call Trace: static_key_enable_cpuslocked+0xf8/0x120 (unreliable) static_key_enable+0x30/0x50 setup_forced_irqthreads+0x28/0x40 do_early_param+0xa0/0x108 parse_args+0x290/0x4e0 parse_early_options+0x48/0x5c parse_early_param+0x58/0x84 early_init_devtree+0xd4/0x518 early_setup+0xb4/0x214 So call jump_label_init() just before parse_early_param() in early_init_devtree(). Suggested-by: Michael Ellerman Signed-off-by: Zhouyi Zhou [mpe: Add call trace to change log and minor wording edits.] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220726015747.11754-1-zhouzhouyi@gmail.com Signed-off-by: Sasha Levin

powerpc/prom: Mark identical_pvr_fixup as __init

2021-05-22T08:57:32Z

[ Upstream commit 1ef1dd9c7ed27b080445e1576e8a05957e0e4dfc ] If identical_pvr_fixup() is not inlined, there are two modpost warnings: WARNING: modpost: vmlinux.o(.text+0x54e8): Section mismatch in reference from the function identical_pvr_fixup() to the function .init.text:of_get_flat_dt_prop() The function identical_pvr_fixup() references the function __init of_get_flat_dt_prop(). This is often because identical_pvr_fixup lacks a __init annotation or the annotation of of_get_flat_dt_prop is wrong. WARNING: modpost: vmlinux.o(.text+0x551c): Section mismatch in reference from the function identical_pvr_fixup() to the function .init.text:identify_cpu() The function identical_pvr_fixup() references the function __init identify_cpu(). This is often because identical_pvr_fixup lacks a __init annotation or the annotation of identify_cpu is wrong. identical_pvr_fixup() calls two functions marked as __init and is only called by a function marked as __init so it should be marked as __init as well. At the same time, remove the inline keywork as it is not necessary to inline this function. The compiler is still free to do so if it feels it is worthwhile since commit 889b3c1245de ("compiler: remove CONFIG_OPTIMIZE_INLINING entirely"). Fixes: 14b3d926a22b ("[POWERPC] 4xx: update 440EP(x)/440GR(x) identical PVR issue workaround") Signed-off-by: Nathan Chancellor Signed-off-by: Michael Ellerman Link: https://github.com/ClangBuiltLinux/linux/issues/1316 Link: https://lore.kernel.org/r/20210302200829.2680663-1-nathan@kernel.org Signed-off-by: Sasha Levin

powerpc/64s: Save FSCR to init_task.thread.fscr after feature init

2020-06-20T08:25:20Z

commit 912c0a7f2b5daa3cbb2bc10f303981e493de73bd upstream. At boot the FSCR is initialised via one of two paths. On most systems it's set to a hard coded value in __init_FSCR(). On newer skiboot systems we use the device tree CPU features binding, where firmware can tell Linux what bits to set in FSCR (and HFSCR). In both cases the value that's configured at boot is not propagated into the init_task.thread.fscr value prior to the initial fork of init (pid 1), which means the value is not used by any processes other than swapper (the idle task). For the __init_FSCR() case this is OK, because the value in init_task.thread.fscr is initialised to something sensible. However it does mean that the value set in __init_FSCR() is not used other than for swapper, which is odd and confusing. The bigger problem is for the device tree CPU features case it prevents firmware from setting (or clearing) FSCR bits for use by user space. This means all existing kernels can not have features enabled/disabled by firmware if those features require setting/clearing FSCR bits. We can handle both cases by saving the FSCR value into init_task.thread.fscr after we have initialised it at boot. This fixes the bug for device tree CPU features, and will allow us to simplify the initialisation for the __init_FSCR() case in a future patch. Fixes: 5a61ef74f269 ("powerpc/64s: Support new device tree binding for discovering CPU features") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200527145843.2761782-3-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman

powerpc/prom: fix early DEBUG messages

2019-12-05T14:37:41Z

[ Upstream commit b18f0ae92b0a1db565c3e505fa87b6971ad3b641 ] This patch fixes early DEBUG messages in prom.c: - Use %px instead of %p to see the addresses - Cast memblock_phys_mem_size() with (unsigned long long) to avoid build failure when phys_addr_t is not 64 bits. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin

powerpc: Fix booting P9 hash with CONFIG_PPC_RADIX_MMU=N

2017-05-25T13:07:44Z

Currently if you disable CONFIG_PPC_RADIX_MMU you'll crash on boot on a P9. This is because we still set MMU_FTR_TYPE_RADIX via ibm,pa-features and MMU_FTR_TYPE_RADIX is what's used for code patching in much of the asm code (ie. slb_miss_realmode) This patch fixes the problem by stopping MMU_FTR_TYPE_RADIX from being set from ibm.pa-features. We may eventually end up removing the CONFIG_PPC_RADIX_MMU option completely but until then this fixes the issue. Fixes: 17a3dd2f5fc7 ("powerpc/mm/radix: Use firmware feature to enable Radix MMU") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Michael Neuling Signed-off-by: Michael Ellerman

powerpc/64s: Support new device tree binding for discovering CPU features

2017-05-09T13:42:55Z

The ibm,powerpc-cpu-features device tree binding describes CPU features with ASCII names and extensible compatibility, privilege, and enablement metadata that allows improved flexibility and compatibility with new hardware. The interface is described in detail in ibm,powerpc-cpu-features.txt in this patch. Currently this code is not enabled by default, and there are no released firmwares that provide the binding. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc: Remove unnecessary includes of asm/debug.h

2017-04-10T21:46:04Z

These files don't seem to have any need for asm/debug.h, now that all it includes are the debugger hooks and breakpoint definitions. Signed-off-by: Michael Ellerman

powerpc: Change places using CONFIG_KEXEC to use CONFIG_KEXEC_CORE instead.

2016-11-30T12:15:11Z

Commit 2965faa5e03d ("kexec: split kexec_load syscall from kexec core code") introduced CONFIG_KEXEC_CORE so that CONFIG_KEXEC means whether the kexec_load system call should be compiled-in and CONFIG_KEXEC_FILE means whether the kexec_file_load system call should be compiled-in. These options can be set independently from each other. Since until now powerpc only supported kexec_load, CONFIG_KEXEC and CONFIG_KEXEC_CORE were synonyms. That is not the case anymore, so we need to make a distinction. Almost all places where CONFIG_KEXEC was being used should be using CONFIG_KEXEC_CORE instead, since kexec_file_load also needs that code compiled in. Signed-off-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman

powerpc/64: Used named initialisers for ibm_pa_features

2016-11-18T12:02:19Z

The ibm_pa_features array consists of structures that describe which bit and byte in the ibm,pa-features property toggles one or more flags in either the CPU, MMU, or user visible feature flags. Each one consists of 7 values, which are all unsigned long, int or char, meaning the compiler gives us no warning if we assign the wrong values to the wrong elements. In fact we have had a bug here in the past, where we were setting incorrect bits, see commit 6997e57d693b ("powerpc: scan_features() updates incorrect bits for REAL_LE"). So switch to using named initialisers for the structure elements, to reduce the likelihood of future bugs, and hopefully improve readability also. Signed-off-by: Michael Ellerman Reviewed-by: Balbir Singh

powerpc/mm: Make MMU_FTR_RADIX a MMU family feature

2016-08-01T01:14:57Z

MMU feature bits are defined such that we use the lower half to present MMU family features. Remove the strict split of half and also move Radix to a mmu family feature. Radix introduce a new MMU model and strictly speaking it is a new MMU family. This also free up bits which can be used for individual features later. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman