Merge tag 'powerpc-5.2-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Slightly delayed due to the issue with printk() calling
  probe_kernel_read() interacting with our new user access prevention
  stuff, but all fixed now.

  The only out-of-area changes are the addition of a cpuhp_state, small
  additions to Documentation and MAINTAINERS updates.

  Highlights:

   - Support for Kernel Userspace Access/Execution Prevention (like
     SMAP/SMEP/PAN/PXN) on some 64-bit and 32-bit CPUs. This prevents
     the kernel from accidentally accessing userspace outside
     copy_to/from_user(), or ever executing userspace.

   - KASAN support on 32-bit.

   - Rework of where we map the kernel, vmalloc, etc. on 64-bit hash to
     use the same address ranges we use with the Radix MMU.

   - A rewrite into C of large parts of our idle handling code for
     64-bit Book3S (ie. power8 & power9).

   - A fast path entry for syscalls on 32-bit CPUs, for a 12-17% speedup
     in the null_syscall benchmark.

   - On 64-bit bare metal we have support for recovering from errors
     with the time base (our clocksource), however if that fails
     currently we hang in __delay() and never crash. We now have support
     for detecting that case and short circuiting __delay() so we at
     least panic() and reboot.

   - Add support for optionally enabling the DAWR on Power9, which had
     to be disabled by default due to a hardware erratum. This has the
     effect of enabling hardware breakpoints for GDB, the downside is a
     badly behaved program could crash the machine by pointing the DAWR
     at cache inhibited memory. This is opt-in obviously.

   - xmon, our crash handler, gets support for a read only mode where
     operations that could change memory or otherwise disturb the system
     are disabled.

  Plus many clean-ups, reworks and minor fixes etc.

  Thanks to: Christophe Leroy, Akshay Adiga, Alastair D'Silva, Alexey
  Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar,
  Anton Blanchard, Ben Hutchings, Bo YU, Breno Leitao, Cédric Le Goater,
  Christopher M. Riedl, Christoph Hellwig, Colin Ian King, David Gibson,
  Ganesh Goudar, Gautham R. Shenoy, George Spelvin, Greg Kroah-Hartman,
  Greg Kurz, Horia Geantă, Jagadeesh Pagadala, Joel Stanley, Joe
  Perches, Julia Lawall, Laurentiu Tudor, Laurent Vivier, Lukas Bulwahn,
  Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael
  Neuling, Mukesh Ojha, Nathan Fontenot, Nathan Lynch, Nicholas Piggin,
  Nick Desaulniers, Oliver O'Halloran, Peng Hao, Qian Cai, Ravi
  Bangoria, Rick Lindsley, Russell Currey, Sachin Sant, Stewart Smith,
  Sukadev Bhattiprolu, Thomas Huth, Tobin C. Harding, Tyrel Datwyler,
  Valentin Schneider, Wei Yongjun, Wen Yang, YueHaibing"

* tag 'powerpc-5.2-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (205 commits)
  powerpc/64s: Use early_mmu_has_feature() in set_kuap()
  powerpc/book3s/64: check for NULL pointer in pgd_alloc()
  powerpc/mm: Fix hugetlb page initialization
  ocxl: Fix return value check in afu_ioctl()
  powerpc/mm: fix section mismatch for setup_kup()
  powerpc/mm: fix redundant inclusion of pgtable-frag.o in Makefile
  powerpc/mm: Fix makefile for KASAN
  powerpc/kasan: add missing/lost Makefile
  selftests/powerpc: Add a signal fuzzer selftest
  powerpc/booke64: set RI in default MSR
  ocxl: Provide global MMIO accessors for external drivers
  ocxl: move event_fd handling to frontend
  ocxl: afu_irq only deals with IRQ IDs, not offsets
  ocxl: Allow external drivers to use OpenCAPI contexts
  ocxl: Create a clear delineation between ocxl backend & frontend
  ocxl: Don't pass pci_dev around
  ocxl: Split pci.c
  ocxl: Remove some unused exported symbols
  ocxl: Remove superfluous 'extern' from headers
  ocxl: read_pasid never returns an error, so make it void
  ...

1 files changed, 246 insertions, 0 deletions

diff --git a/arch/powerpc/mm/nohash/44x.c b/arch/powerpc/mm/nohash/44x.c
new file mode 100644
index 000000000000..c07983ebc02e
--- /dev/null
+++ b/arch/powerpc/mm/nohash/44x.c
@@ -0,0 +1,246 @@
+/*
+ * Modifications by Matt Porter (mporter@mvista.com) to support
+ * PPC44x Book E processors.
+ *
+ * This file contains the routines for initializing the MMU
+ * on the 4xx series of chips.
+ *  -- paulus
+ *
+ *  Derived from arch/ppc/mm/init.c:
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ *    Copyright (C) 1996 Paul Mackerras
+ *
+ *  Derived from "arch/i386/mm/init.c"
+ *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/memblock.h>
+
+#include <asm/mmu.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/code-patching.h>
+
+#include <mm/mmu_decl.h>
+
+/* Used by the 44x TLB replacement exception handler.
+ * Just needed it declared someplace.
+ */
+unsigned int tlb_44x_index; /* = 0 */
+unsigned int tlb_44x_hwater = PPC44x_TLB_SIZE - 1 - PPC44x_EARLY_TLBS;
+int icache_44x_need_flush;
+
+unsigned long tlb_47x_boltmap[1024/8];
+
+static void ppc44x_update_tlb_hwater(void)
+{
+	/* The TLB miss handlers hard codes the watermark in a cmpli
+	 * instruction to improve performances rather than loading it
+	 * from the global variable. Thus, we patch the instructions
+	 * in the 2 TLB miss handlers when updating the value
+	 */
+	modify_instruction_site(&patch__tlb_44x_hwater_D, 0xffff, tlb_44x_hwater);
+	modify_instruction_site(&patch__tlb_44x_hwater_I, 0xffff, tlb_44x_hwater);
+}
+
+/*
+ * "Pins" a 256MB TLB entry in AS0 for kernel lowmem for 44x type MMU
+ */
+static void __init ppc44x_pin_tlb(unsigned int virt, unsigned int phys)
+{
+	unsigned int entry = tlb_44x_hwater--;
+
+	ppc44x_update_tlb_hwater();
+
+	mtspr(SPRN_MMUCR, 0);
+
+	__asm__ __volatile__(
+		"tlbwe	%2,%3,%4\n"
+		"tlbwe	%1,%3,%5\n"
+		"tlbwe	%0,%3,%6\n"
+	:
+	: "r" (PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G),
+	  "r" (phys),
+	  "r" (virt | PPC44x_TLB_VALID | PPC44x_TLB_256M),
+	  "r" (entry),
+	  "i" (PPC44x_TLB_PAGEID),
+	  "i" (PPC44x_TLB_XLAT),
+	  "i" (PPC44x_TLB_ATTRIB));
+}
+
+static int __init ppc47x_find_free_bolted(void)
+{
+	unsigned int mmube0 = mfspr(SPRN_MMUBE0);
+	unsigned int mmube1 = mfspr(SPRN_MMUBE1);
+
+	if (!(mmube0 & MMUBE0_VBE0))
+		return 0;
+	if (!(mmube0 & MMUBE0_VBE1))
+		return 1;
+	if (!(mmube0 & MMUBE0_VBE2))
+		return 2;
+	if (!(mmube1 & MMUBE1_VBE3))
+		return 3;
+	if (!(mmube1 & MMUBE1_VBE4))
+		return 4;
+	if (!(mmube1 & MMUBE1_VBE5))
+		return 5;
+	return -1;
+}
+
+static void __init ppc47x_update_boltmap(void)
+{
+	unsigned int mmube0 = mfspr(SPRN_MMUBE0);
+	unsigned int mmube1 = mfspr(SPRN_MMUBE1);
+
+	if (mmube0 & MMUBE0_VBE0)
+		__set_bit((mmube0 >> MMUBE0_IBE0_SHIFT) & 0xff,
+			  tlb_47x_boltmap);
+	if (mmube0 & MMUBE0_VBE1)
+		__set_bit((mmube0 >> MMUBE0_IBE1_SHIFT) & 0xff,
+			  tlb_47x_boltmap);
+	if (mmube0 & MMUBE0_VBE2)
+		__set_bit((mmube0 >> MMUBE0_IBE2_SHIFT) & 0xff,
+			  tlb_47x_boltmap);
+	if (mmube1 & MMUBE1_VBE3)
+		__set_bit((mmube1 >> MMUBE1_IBE3_SHIFT) & 0xff,
+			  tlb_47x_boltmap);
+	if (mmube1 & MMUBE1_VBE4)
+		__set_bit((mmube1 >> MMUBE1_IBE4_SHIFT) & 0xff,
+			  tlb_47x_boltmap);
+	if (mmube1 & MMUBE1_VBE5)
+		__set_bit((mmube1 >> MMUBE1_IBE5_SHIFT) & 0xff,
+			  tlb_47x_boltmap);
+}
+
+/*
+ * "Pins" a 256MB TLB entry in AS0 for kernel lowmem for 47x type MMU
+ */
+static void ppc47x_pin_tlb(unsigned int virt, unsigned int phys)
+{
+	unsigned int rA;
+	int bolted;
+
+	/* Base rA is HW way select, way 0, bolted bit set */
+	rA = 0x88000000;
+
+	/* Look for a bolted entry slot */
+	bolted = ppc47x_find_free_bolted();
+	BUG_ON(bolted < 0);
+
+	/* Insert bolted slot number */
+	rA |= bolted << 24;
+
+	pr_debug("256M TLB entry for 0x%08x->0x%08x in bolt slot %d\n",
+		 virt, phys, bolted);
+
+	mtspr(SPRN_MMUCR, 0);
+
+	__asm__ __volatile__(
+		"tlbwe	%2,%3,0\n"
+		"tlbwe	%1,%3,1\n"
+		"tlbwe	%0,%3,2\n"
+		:
+		: "r" (PPC47x_TLB2_SW | PPC47x_TLB2_SR |
+		       PPC47x_TLB2_SX
+#ifdef CONFIG_SMP
+		       | PPC47x_TLB2_M
+#endif
+		       ),
+		  "r" (phys),
+		  "r" (virt | PPC47x_TLB0_VALID | PPC47x_TLB0_256M),
+		  "r" (rA));
+}
+
+void __init MMU_init_hw(void)
+{
+	/* This is not useful on 47x but won't hurt either */
+	ppc44x_update_tlb_hwater();
+
+	flush_instruction_cache();
+}
+
+unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
+{
+	unsigned long addr;
+	unsigned long memstart = memstart_addr & ~(PPC_PIN_SIZE - 1);
+
+	/* Pin in enough TLBs to cover any lowmem not covered by the
+	 * initial 256M mapping established in head_44x.S */
+	for (addr = memstart + PPC_PIN_SIZE; addr < lowmem_end_addr;
+	     addr += PPC_PIN_SIZE) {
+		if (mmu_has_feature(MMU_FTR_TYPE_47x))
+			ppc47x_pin_tlb(addr + PAGE_OFFSET, addr);
+		else
+			ppc44x_pin_tlb(addr + PAGE_OFFSET, addr);
+	}
+	if (mmu_has_feature(MMU_FTR_TYPE_47x)) {
+		ppc47x_update_boltmap();
+
+#ifdef DEBUG
+		{
+			int i;
+
+			printk(KERN_DEBUG "bolted entries: ");
+			for (i = 0; i < 255; i++) {
+				if (test_bit(i, tlb_47x_boltmap))
+					printk("%d ", i);
+			}
+			printk("\n");
+		}
+#endif /* DEBUG */
+	}
+	return total_lowmem;
+}
+
+void setup_initial_memory_limit(phys_addr_t first_memblock_base,
+				phys_addr_t first_memblock_size)
+{
+	u64 size;
+
+#ifndef CONFIG_NONSTATIC_KERNEL
+	/* We don't currently support the first MEMBLOCK not mapping 0
+	 * physical on those processors
+	 */
+	BUG_ON(first_memblock_base != 0);
+#endif
+
+	/* 44x has a 256M TLB entry pinned at boot */
+	size = (min_t(u64, first_memblock_size, PPC_PIN_SIZE));
+	memblock_set_current_limit(first_memblock_base + size);
+}
+
+#ifdef CONFIG_SMP
+void __init mmu_init_secondary(int cpu)
+{
+	unsigned long addr;
+	unsigned long memstart = memstart_addr & ~(PPC_PIN_SIZE - 1);
+
+	/* Pin in enough TLBs to cover any lowmem not covered by the
+	 * initial 256M mapping established in head_44x.S
+	 *
+	 * WARNING: This is called with only the first 256M of the
+	 * linear mapping in the TLB and we can't take faults yet
+	 * so beware of what this code uses. It runs off a temporary
+	 * stack. current (r2) isn't initialized, smp_processor_id()
+	 * will not work, current thread info isn't accessible, ...
+	 */
+	for (addr = memstart + PPC_PIN_SIZE; addr < lowmem_end_addr;
+	     addr += PPC_PIN_SIZE) {
+		if (mmu_has_feature(MMU_FTR_TYPE_47x))
+			ppc47x_pin_tlb(addr + PAGE_OFFSET, addr);
+		else
+			ppc44x_pin_tlb(addr + PAGE_OFFSET, addr);
+	}
+}
+#endif /* CONFIG_SMP */