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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/powerpc/mm/nohash/e500_hugetlbpage.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/mm/nohash/e500_hugetlbpage.c')
-rw-r--r--arch/powerpc/mm/nohash/e500_hugetlbpage.c190
1 files changed, 190 insertions, 0 deletions
diff --git a/arch/powerpc/mm/nohash/e500_hugetlbpage.c b/arch/powerpc/mm/nohash/e500_hugetlbpage.c
new file mode 100644
index 000000000..c7d4b317a
--- /dev/null
+++ b/arch/powerpc/mm/nohash/e500_hugetlbpage.c
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PPC Huge TLB Page Support for Book3E MMU
+ *
+ * Copyright (C) 2009 David Gibson, IBM Corporation.
+ * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor
+ *
+ */
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+
+#include <asm/mmu.h>
+
+#ifdef CONFIG_PPC64
+#include <asm/paca.h>
+
+static inline int tlb1_next(void)
+{
+ struct paca_struct *paca = get_paca();
+ struct tlb_core_data *tcd;
+ int this, next;
+
+ tcd = paca->tcd_ptr;
+ this = tcd->esel_next;
+
+ next = this + 1;
+ if (next >= tcd->esel_max)
+ next = tcd->esel_first;
+
+ tcd->esel_next = next;
+ return this;
+}
+
+static inline void book3e_tlb_lock(void)
+{
+ struct paca_struct *paca = get_paca();
+ unsigned long tmp;
+ int token = smp_processor_id() + 1;
+
+ /*
+ * Besides being unnecessary in the absence of SMT, this
+ * check prevents trying to do lbarx/stbcx. on e5500 which
+ * doesn't implement either feature.
+ */
+ if (!cpu_has_feature(CPU_FTR_SMT))
+ return;
+
+ asm volatile("1: lbarx %0, 0, %1;"
+ "cmpwi %0, 0;"
+ "bne 2f;"
+ "stbcx. %2, 0, %1;"
+ "bne 1b;"
+ "b 3f;"
+ "2: lbzx %0, 0, %1;"
+ "cmpwi %0, 0;"
+ "bne 2b;"
+ "b 1b;"
+ "3:"
+ : "=&r" (tmp)
+ : "r" (&paca->tcd_ptr->lock), "r" (token)
+ : "memory");
+}
+
+static inline void book3e_tlb_unlock(void)
+{
+ struct paca_struct *paca = get_paca();
+
+ if (!cpu_has_feature(CPU_FTR_SMT))
+ return;
+
+ isync();
+ paca->tcd_ptr->lock = 0;
+}
+#else
+static inline int tlb1_next(void)
+{
+ int index, ncams;
+
+ ncams = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY;
+
+ index = this_cpu_read(next_tlbcam_idx);
+
+ /* Just round-robin the entries and wrap when we hit the end */
+ if (unlikely(index == ncams - 1))
+ __this_cpu_write(next_tlbcam_idx, tlbcam_index);
+ else
+ __this_cpu_inc(next_tlbcam_idx);
+
+ return index;
+}
+
+static inline void book3e_tlb_lock(void)
+{
+}
+
+static inline void book3e_tlb_unlock(void)
+{
+}
+#endif
+
+static inline int book3e_tlb_exists(unsigned long ea, unsigned long pid)
+{
+ int found = 0;
+
+ mtspr(SPRN_MAS6, pid << 16);
+ asm volatile(
+ "tlbsx 0,%1\n"
+ "mfspr %0,0x271\n"
+ "srwi %0,%0,31\n"
+ : "=&r"(found) : "r"(ea));
+
+ return found;
+}
+
+static void
+book3e_hugetlb_preload(struct vm_area_struct *vma, unsigned long ea, pte_t pte)
+{
+ unsigned long mas1, mas2;
+ u64 mas7_3;
+ unsigned long psize, tsize, shift;
+ unsigned long flags;
+ struct mm_struct *mm;
+ int index;
+
+ if (unlikely(is_kernel_addr(ea)))
+ return;
+
+ mm = vma->vm_mm;
+
+ psize = vma_mmu_pagesize(vma);
+ shift = __ilog2(psize);
+ tsize = shift - 10;
+ /*
+ * We can't be interrupted while we're setting up the MAS
+ * registers or after we've confirmed that no tlb exists.
+ */
+ local_irq_save(flags);
+
+ book3e_tlb_lock();
+
+ if (unlikely(book3e_tlb_exists(ea, mm->context.id))) {
+ book3e_tlb_unlock();
+ local_irq_restore(flags);
+ return;
+ }
+
+ /* We have to use the CAM(TLB1) on FSL parts for hugepages */
+ index = tlb1_next();
+ mtspr(SPRN_MAS0, MAS0_ESEL(index) | MAS0_TLBSEL(1));
+
+ mas1 = MAS1_VALID | MAS1_TID(mm->context.id) | MAS1_TSIZE(tsize);
+ mas2 = ea & ~((1UL << shift) - 1);
+ mas2 |= (pte_val(pte) >> PTE_WIMGE_SHIFT) & MAS2_WIMGE_MASK;
+ mas7_3 = (u64)pte_pfn(pte) << PAGE_SHIFT;
+ mas7_3 |= (pte_val(pte) >> PTE_BAP_SHIFT) & MAS3_BAP_MASK;
+ if (!pte_dirty(pte))
+ mas7_3 &= ~(MAS3_SW|MAS3_UW);
+
+ mtspr(SPRN_MAS1, mas1);
+ mtspr(SPRN_MAS2, mas2);
+
+ if (mmu_has_feature(MMU_FTR_BIG_PHYS))
+ mtspr(SPRN_MAS7, upper_32_bits(mas7_3));
+ mtspr(SPRN_MAS3, lower_32_bits(mas7_3));
+
+ asm volatile ("tlbwe");
+
+ book3e_tlb_unlock();
+ local_irq_restore(flags);
+}
+
+/*
+ * This is called at the end of handling a user page fault, when the
+ * fault has been handled by updating a PTE in the linux page tables.
+ *
+ * This must always be called with the pte lock held.
+ */
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
+{
+ if (is_vm_hugetlb_page(vma))
+ book3e_hugetlb_preload(vma, address, *ptep);
+}
+
+void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+ struct hstate *hstate = hstate_file(vma->vm_file);
+ unsigned long tsize = huge_page_shift(hstate) - 10;
+
+ __flush_tlb_page(vma->vm_mm, vmaddr, tsize, 0);
+}