From e0c827aca0730b51f38081aa4e8ecf0912aab55f Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sat, 10 Nov 2018 13:16:51 +0200 Subject: drm/omap: Populate DSS children in omapdss driver The DSS DT node contains children that describe the DSS components (DISPC and internal encoders). Each of those components is handled by a platform driver, and thus needs to be backed by a platform device. The corresponding platform devices are created in mach-omap2 code by a call to of_platform_populate(). While this approach has worked so far, it doesn't model the hardware architecture very well, as it creates child devices before the parent is ready to handle them. This would be akin to creating I2C slaves before the I2C master is available. The task can be easily performed in the omapdss driver code instead, simplifying mach-omap2 code. We however can't remove the mach-omap2 code completely as the omap2fb driver still depends on it, but we can move it to the omap2fb-specific section, where it can stay until the omap2fb driver gets removed. This has the added benefit of not allowing DSS components to probe before the DSS itself, which led to runtime PM issues when the DSS probe is deferred. Fixes: 27d624527d99 ("drm/omap: dss: Acquire next dssdev at probe time") Signed-off-by: Laurent Pinchart Acked-by: Tony Lindgren Reviewed-by: Sebastian Reichel Signed-off-by: Tomi Valkeinen Link: https://patchwork.freedesktop.org/patch/msgid/20181110111654.4387-2-laurent.pinchart@ideasonboard.com --- arch/arm/mach-omap2/display.c | 111 ++++++++++++++++++++---------------------- 1 file changed, 53 insertions(+), 58 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/mach-omap2/display.c b/arch/arm/mach-omap2/display.c index 9500b6e27380..f86b72d1d59e 100644 --- a/arch/arm/mach-omap2/display.c +++ b/arch/arm/mach-omap2/display.c @@ -209,11 +209,61 @@ static int __init omapdss_init_fbdev(void) return 0; } -#else -static inline int omapdss_init_fbdev(void) + +static const char * const omapdss_compat_names[] __initconst = { + "ti,omap2-dss", + "ti,omap3-dss", + "ti,omap4-dss", + "ti,omap5-dss", + "ti,dra7-dss", +}; + +static struct device_node * __init omapdss_find_dss_of_node(void) { - return 0; + struct device_node *node; + int i; + + for (i = 0; i < ARRAY_SIZE(omapdss_compat_names); ++i) { + node = of_find_compatible_node(NULL, NULL, + omapdss_compat_names[i]); + if (node) + return node; + } + + return NULL; } + +static int __init omapdss_init_of(void) +{ + int r; + struct device_node *node; + struct platform_device *pdev; + + /* only create dss helper devices if dss is enabled in the .dts */ + + node = omapdss_find_dss_of_node(); + if (!node) + return 0; + + if (!of_device_is_available(node)) + return 0; + + pdev = of_find_device_by_node(node); + + if (!pdev) { + pr_err("Unable to find DSS platform device\n"); + return -ENODEV; + } + + r = of_platform_populate(node, NULL, NULL, &pdev->dev); + if (r) { + pr_err("Unable to populate DSS submodule devices\n"); + return r; + } + + return omapdss_init_fbdev(); +} +omap_device_initcall(omapdss_init_of); #endif /* CONFIG_FB_OMAP2 */ static void dispc_disable_outputs(void) @@ -361,58 +411,3 @@ int omap_dss_reset(struct omap_hwmod *oh) return r; } - -static const char * const omapdss_compat_names[] __initconst = { - "ti,omap2-dss", - "ti,omap3-dss", - "ti,omap4-dss", - "ti,omap5-dss", - "ti,dra7-dss", -}; - -static struct device_node * __init omapdss_find_dss_of_node(void) -{ - struct device_node *node; - int i; - - for (i = 0; i < ARRAY_SIZE(omapdss_compat_names); ++i) { - node = of_find_compatible_node(NULL, NULL, - omapdss_compat_names[i]); - if (node) - return node; - } - - return NULL; -} - -static int __init omapdss_init_of(void) -{ - int r; - struct device_node *node; - struct platform_device *pdev; - - /* only create dss helper devices if dss is enabled in the .dts */ - - node = omapdss_find_dss_of_node(); - if (!node) - return 0; - - if (!of_device_is_available(node)) - return 0; - - pdev = of_find_device_by_node(node); - - if (!pdev) { - pr_err("Unable to find DSS platform device\n"); - return -ENODEV; - } - - r = of_platform_populate(node, NULL, NULL, &pdev->dev); - if (r) { - pr_err("Unable to populate DSS submodule devices\n"); - return r; - } - - return omapdss_init_fbdev(); -} -omap_device_initcall(omapdss_init_of); -- cgit v1.2.3-59-g8ed1b From 899a42f836678a595f7d2bc36a5a0c2b03d08cbc Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 19 Jul 2018 11:42:36 +0100 Subject: ARM: make lookup_processor_type() non-__init Move lookup_processor_type() out of the __init section so it is callable from (eg) the secondary startup code during hotplug. Reviewed-by: Julien Thierry Signed-off-by: Russell King --- arch/arm/kernel/head-common.S | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 6e0375e7db05..997b02302c31 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -145,6 +145,9 @@ __mmap_switched_data: #endif .size __mmap_switched_data, . - __mmap_switched_data + __FINIT + .text + /* * This provides a C-API version of __lookup_processor_type */ @@ -156,9 +159,6 @@ ENTRY(lookup_processor_type) ldmfd sp!, {r4 - r6, r9, pc} ENDPROC(lookup_processor_type) - __FINIT - .text - /* * Read processor ID register (CP#15, CR0), and look up in the linker-built * supported processor list. Note that we can't use the absolute addresses -- cgit v1.2.3-59-g8ed1b From 65987a8553061515b5851b472081aedb9837a391 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 19 Jul 2018 11:59:56 +0100 Subject: ARM: split out processor lookup Split out the lookup of the processor type and associated error handling from the rest of setup_processor() - we will need to use this in the secondary CPU bringup path for big.Little Spectre variant 2 mitigation. Reviewed-by: Julien Thierry Signed-off-by: Russell King --- arch/arm/include/asm/cputype.h | 1 + arch/arm/kernel/setup.c | 31 +++++++++++++++++++------------ 2 files changed, 20 insertions(+), 12 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index 26021980504d..f6df4bb4e543 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h @@ -107,6 +107,7 @@ #define ARM_CPU_PART_SCORPION 0x510002d0 extern unsigned int processor_id; +struct proc_info_list *lookup_processor(u32 midr); #ifdef CONFIG_CPU_CP15 #define read_cpuid(reg) \ diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index fc40a2b40595..05a4eb6b0d01 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -667,22 +667,29 @@ static void __init smp_build_mpidr_hash(void) } #endif -static void __init setup_processor(void) +/* + * locate processor in the list of supported processor types. The linker + * builds this table for us from the entries in arch/arm/mm/proc-*.S + */ +struct proc_info_list *lookup_processor(u32 midr) { - struct proc_info_list *list; + struct proc_info_list *list = lookup_processor_type(midr); - /* - * locate processor in the list of supported processor - * types. The linker builds this table for us from the - * entries in arch/arm/mm/proc-*.S - */ - list = lookup_processor_type(read_cpuid_id()); if (!list) { - pr_err("CPU configuration botched (ID %08x), unable to continue.\n", - read_cpuid_id()); - while (1); + pr_err("CPU%u: configuration botched (ID %08x), CPU halted\n", + smp_processor_id(), midr); + while (1) + /* can't use cpu_relax() here as it may require MMU setup */; } + return list; +} + +static void __init setup_processor(void) +{ + unsigned int midr = read_cpuid_id(); + struct proc_info_list *list = lookup_processor(midr); + cpu_name = list->cpu_name; __cpu_architecture = __get_cpu_architecture(); @@ -700,7 +707,7 @@ static void __init setup_processor(void) #endif pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n", - cpu_name, read_cpuid_id(), read_cpuid_id() & 15, + list->cpu_name, midr, midr & 15, proc_arch[cpu_architecture()], get_cr()); snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c", -- cgit v1.2.3-59-g8ed1b From 945aceb1db8885d3a35790cf2e810f681db52756 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 19 Jul 2018 12:43:03 +0100 Subject: ARM: clean up per-processor check_bugs method call Call the per-processor type check_bugs() method in the same way as we do other per-processor functions - move the "processor." detail into proc-fns.h. Reviewed-by: Julien Thierry Signed-off-by: Russell King --- arch/arm/include/asm/proc-fns.h | 1 + arch/arm/kernel/bugs.c | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h index e25f4392e1b2..30c499146320 100644 --- a/arch/arm/include/asm/proc-fns.h +++ b/arch/arm/include/asm/proc-fns.h @@ -99,6 +99,7 @@ extern void cpu_do_suspend(void *); extern void cpu_do_resume(void *); #else #define cpu_proc_init processor._proc_init +#define cpu_check_bugs processor.check_bugs #define cpu_proc_fin processor._proc_fin #define cpu_reset processor.reset #define cpu_do_idle processor._do_idle diff --git a/arch/arm/kernel/bugs.c b/arch/arm/kernel/bugs.c index 7be511310191..d41d3598e5e5 100644 --- a/arch/arm/kernel/bugs.c +++ b/arch/arm/kernel/bugs.c @@ -6,8 +6,8 @@ void check_other_bugs(void) { #ifdef MULTI_CPU - if (processor.check_bugs) - processor.check_bugs(); + if (cpu_check_bugs) + cpu_check_bugs(); #endif } -- cgit v1.2.3-59-g8ed1b From e209950fdd065d2cc46e6338e47e52841b830cba Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 19 Jul 2018 12:17:38 +0100 Subject: ARM: add PROC_VTABLE and PROC_TABLE macros Allow the way we access members of the processor vtable to be changed at compile time. We will need to move to per-CPU vtables to fix the Spectre variant 2 issues on big.Little systems. However, we have a couple of calls that do not need the vtable treatment, and indeed cause a kernel warning due to the (later) use of smp_processor_id(), so also introduce the PROC_TABLE macro for these which always use CPU 0's function pointers. Reviewed-by: Julien Thierry Signed-off-by: Russell King --- arch/arm/include/asm/proc-fns.h | 39 ++++++++++++++++++++++++++------------- arch/arm/kernel/setup.c | 4 +--- 2 files changed, 27 insertions(+), 16 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h index 30c499146320..c259cc49c641 100644 --- a/arch/arm/include/asm/proc-fns.h +++ b/arch/arm/include/asm/proc-fns.h @@ -23,7 +23,7 @@ struct mm_struct; /* * Don't change this structure - ASM code relies on it. */ -extern struct processor { +struct processor { /* MISC * get data abort address/flags */ @@ -79,9 +79,13 @@ extern struct processor { unsigned int suspend_size; void (*do_suspend)(void *); void (*do_resume)(void *); -} processor; +}; #ifndef MULTI_CPU +static inline void init_proc_vtable(const struct processor *p) +{ +} + extern void cpu_proc_init(void); extern void cpu_proc_fin(void); extern int cpu_do_idle(void); @@ -98,18 +102,27 @@ extern void cpu_reset(unsigned long addr, bool hvc) __attribute__((noreturn)); extern void cpu_do_suspend(void *); extern void cpu_do_resume(void *); #else -#define cpu_proc_init processor._proc_init -#define cpu_check_bugs processor.check_bugs -#define cpu_proc_fin processor._proc_fin -#define cpu_reset processor.reset -#define cpu_do_idle processor._do_idle -#define cpu_dcache_clean_area processor.dcache_clean_area -#define cpu_set_pte_ext processor.set_pte_ext -#define cpu_do_switch_mm processor.switch_mm -/* These three are private to arch/arm/kernel/suspend.c */ -#define cpu_do_suspend processor.do_suspend -#define cpu_do_resume processor.do_resume +extern struct processor processor; +#define PROC_VTABLE(f) processor.f +#define PROC_TABLE(f) processor.f +static inline void init_proc_vtable(const struct processor *p) +{ + processor = *p; +} + +#define cpu_proc_init PROC_VTABLE(_proc_init) +#define cpu_check_bugs PROC_VTABLE(check_bugs) +#define cpu_proc_fin PROC_VTABLE(_proc_fin) +#define cpu_reset PROC_VTABLE(reset) +#define cpu_do_idle PROC_VTABLE(_do_idle) +#define cpu_dcache_clean_area PROC_TABLE(dcache_clean_area) +#define cpu_set_pte_ext PROC_TABLE(set_pte_ext) +#define cpu_do_switch_mm PROC_VTABLE(switch_mm) + +/* These two are private to arch/arm/kernel/suspend.c */ +#define cpu_do_suspend PROC_VTABLE(do_suspend) +#define cpu_do_resume PROC_VTABLE(do_resume) #endif extern void cpu_resume(void); diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 05a4eb6b0d01..c214bd14a1fe 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -693,9 +693,7 @@ static void __init setup_processor(void) cpu_name = list->cpu_name; __cpu_architecture = __get_cpu_architecture(); -#ifdef MULTI_CPU - processor = *list->proc; -#endif + init_proc_vtable(list->proc); #ifdef MULTI_TLB cpu_tlb = *list->tlb; #endif -- cgit v1.2.3-59-g8ed1b From 5df7a99bdd0de4a0480320264c44c04543c29d5a Mon Sep 17 00:00:00 2001 From: Julien Thierry Date: Thu, 8 Nov 2018 17:25:28 +0100 Subject: ARM: 8810/1: vfp: Fix wrong assignement to ufp_exc In vfp_preserve_user_clear_hwstate, ufp_exc->fpinst2 gets assigned to itself. It should actually be hwstate->fpinst2 that gets assigned to the ufp_exc field. Fixes commit 3aa2df6ec2ca6bc143a65351cca4266d03a8bc41 ("ARM: 8791/1: vfp: use __copy_to_user() when saving VFP state"). Reported-by: David Binderman Signed-off-by: Julien Thierry Signed-off-by: Russell King --- arch/arm/vfp/vfpmodule.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm') diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 3b75f1d8a491..15bc3cf2a7fd 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -579,7 +579,7 @@ int vfp_preserve_user_clear_hwstate(struct user_vfp *ufp, */ ufp_exc->fpexc = hwstate->fpexc; ufp_exc->fpinst = hwstate->fpinst; - ufp_exc->fpinst2 = ufp_exc->fpinst2; + ufp_exc->fpinst2 = hwstate->fpinst2; /* Ensure that VFP is disabled. */ vfp_flush_hwstate(thread); -- cgit v1.2.3-59-g8ed1b From 383fb3ee8024d596f488d2dbaf45e572897acbdb Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 19 Jul 2018 12:21:31 +0100 Subject: ARM: spectre-v2: per-CPU vtables to work around big.Little systems In big.Little systems, some CPUs require the Spectre workarounds in paths such as the context switch, but other CPUs do not. In order to handle these differences, we need per-CPU vtables. We are unable to use the kernel's per-CPU variables to support this as per-CPU is not initialised at times when we need access to the vtables, so we have to use an array indexed by logical CPU number. We use an array-of-pointers to avoid having function pointers in the kernel's read/write .data section. Reviewed-by: Julien Thierry Signed-off-by: Russell King --- arch/arm/include/asm/proc-fns.h | 23 +++++++++++++++++++++++ arch/arm/kernel/setup.c | 5 +++++ arch/arm/kernel/smp.c | 31 +++++++++++++++++++++++++++++++ arch/arm/mm/proc-v7-bugs.c | 17 ++--------------- 4 files changed, 61 insertions(+), 15 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h index c259cc49c641..e1b6f280ab08 100644 --- a/arch/arm/include/asm/proc-fns.h +++ b/arch/arm/include/asm/proc-fns.h @@ -104,12 +104,35 @@ extern void cpu_do_resume(void *); #else extern struct processor processor; +#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR) +#include +/* + * This can't be a per-cpu variable because we need to access it before + * per-cpu has been initialised. We have a couple of functions that are + * called in a pre-emptible context, and so can't use smp_processor_id() + * there, hence PROC_TABLE(). We insist in init_proc_vtable() that the + * function pointers for these are identical across all CPUs. + */ +extern struct processor *cpu_vtable[]; +#define PROC_VTABLE(f) cpu_vtable[smp_processor_id()]->f +#define PROC_TABLE(f) cpu_vtable[0]->f +static inline void init_proc_vtable(const struct processor *p) +{ + unsigned int cpu = smp_processor_id(); + *cpu_vtable[cpu] = *p; + WARN_ON_ONCE(cpu_vtable[cpu]->dcache_clean_area != + cpu_vtable[0]->dcache_clean_area); + WARN_ON_ONCE(cpu_vtable[cpu]->set_pte_ext != + cpu_vtable[0]->set_pte_ext); +} +#else #define PROC_VTABLE(f) processor.f #define PROC_TABLE(f) processor.f static inline void init_proc_vtable(const struct processor *p) { processor = *p; } +#endif #define cpu_proc_init PROC_VTABLE(_proc_init) #define cpu_check_bugs PROC_VTABLE(check_bugs) diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index c214bd14a1fe..cd46a595422c 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -115,6 +115,11 @@ EXPORT_SYMBOL(elf_hwcap2); #ifdef MULTI_CPU struct processor processor __ro_after_init; +#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR) +struct processor *cpu_vtable[NR_CPUS] = { + [0] = &processor, +}; +#endif #endif #ifdef MULTI_TLB struct cpu_tlb_fns cpu_tlb __ro_after_init; diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 5ad0b67b9e33..82b879db32ee 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -42,6 +42,7 @@ #include #include #include +#include #include #include #include @@ -102,6 +103,30 @@ static unsigned long get_arch_pgd(pgd_t *pgd) #endif } +#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR) +static int secondary_biglittle_prepare(unsigned int cpu) +{ + if (!cpu_vtable[cpu]) + cpu_vtable[cpu] = kzalloc(sizeof(*cpu_vtable[cpu]), GFP_KERNEL); + + return cpu_vtable[cpu] ? 0 : -ENOMEM; +} + +static void secondary_biglittle_init(void) +{ + init_proc_vtable(lookup_processor(read_cpuid_id())->proc); +} +#else +static int secondary_biglittle_prepare(unsigned int cpu) +{ + return 0; +} + +static void secondary_biglittle_init(void) +{ +} +#endif + int __cpu_up(unsigned int cpu, struct task_struct *idle) { int ret; @@ -109,6 +134,10 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) if (!smp_ops.smp_boot_secondary) return -ENOSYS; + ret = secondary_biglittle_prepare(cpu); + if (ret) + return ret; + /* * We need to tell the secondary core where to find * its stack and the page tables. @@ -360,6 +389,8 @@ asmlinkage void secondary_start_kernel(void) struct mm_struct *mm = &init_mm; unsigned int cpu; + secondary_biglittle_init(); + /* * The identity mapping is uncached (strongly ordered), so * switch away from it before attempting any exclusive accesses. diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c index 5544b82a2e7a..9a07916af8dd 100644 --- a/arch/arm/mm/proc-v7-bugs.c +++ b/arch/arm/mm/proc-v7-bugs.c @@ -52,8 +52,6 @@ static void cpu_v7_spectre_init(void) case ARM_CPU_PART_CORTEX_A17: case ARM_CPU_PART_CORTEX_A73: case ARM_CPU_PART_CORTEX_A75: - if (processor.switch_mm != cpu_v7_bpiall_switch_mm) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = harden_branch_predictor_bpiall; spectre_v2_method = "BPIALL"; @@ -61,8 +59,6 @@ static void cpu_v7_spectre_init(void) case ARM_CPU_PART_CORTEX_A15: case ARM_CPU_PART_BRAHMA_B15: - if (processor.switch_mm != cpu_v7_iciallu_switch_mm) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = harden_branch_predictor_iciallu; spectre_v2_method = "ICIALLU"; @@ -88,11 +84,9 @@ static void cpu_v7_spectre_init(void) ARM_SMCCC_ARCH_WORKAROUND_1, &res); if ((int)res.a0 != 0) break; - if (processor.switch_mm != cpu_v7_hvc_switch_mm && cpu) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = call_hvc_arch_workaround_1; - processor.switch_mm = cpu_v7_hvc_switch_mm; + cpu_do_switch_mm = cpu_v7_hvc_switch_mm; spectre_v2_method = "hypervisor"; break; @@ -101,11 +95,9 @@ static void cpu_v7_spectre_init(void) ARM_SMCCC_ARCH_WORKAROUND_1, &res); if ((int)res.a0 != 0) break; - if (processor.switch_mm != cpu_v7_smc_switch_mm && cpu) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = call_smc_arch_workaround_1; - processor.switch_mm = cpu_v7_smc_switch_mm; + cpu_do_switch_mm = cpu_v7_smc_switch_mm; spectre_v2_method = "firmware"; break; @@ -119,11 +111,6 @@ static void cpu_v7_spectre_init(void) if (spectre_v2_method) pr_info("CPU%u: Spectre v2: using %s workaround\n", smp_processor_id(), spectre_v2_method); - return; - -bl_error: - pr_err("CPU%u: Spectre v2: incorrect context switching function, system vulnerable\n", - cpu); } #else static void cpu_v7_spectre_init(void) -- cgit v1.2.3-59-g8ed1b