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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/powerpc/kernel/paca.c
Initial import
Diffstat (limited to 'arch/powerpc/kernel/paca.c')
-rw-r--r--arch/powerpc/kernel/paca.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
new file mode 100644
index 000000000..5a23b69f8
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+++ b/arch/powerpc/kernel/paca.c
@@ -0,0 +1,250 @@
+/*
+ * c 2001 PPC 64 Team, IBM Corp
+ *
+ * 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/smp.h>
+#include <linux/export.h>
+#include <linux/memblock.h>
+
+#include <asm/lppaca.h>
+#include <asm/paca.h>
+#include <asm/sections.h>
+#include <asm/pgtable.h>
+#include <asm/kexec.h>
+
+/* This symbol is provided by the linker - let it fill in the paca
+ * field correctly */
+extern unsigned long __toc_start;
+
+#ifdef CONFIG_PPC_BOOK3S
+
+/*
+ * The structure which the hypervisor knows about - this structure
+ * should not cross a page boundary. The vpa_init/register_vpa call
+ * is now known to fail if the lppaca structure crosses a page
+ * boundary. The lppaca is also used on POWER5 pSeries boxes.
+ * The lppaca is 640 bytes long, and cannot readily
+ * change since the hypervisor knows its layout, so a 1kB alignment
+ * will suffice to ensure that it doesn't cross a page boundary.
+ */
+struct lppaca lppaca[] = {
+ [0 ... (NR_LPPACAS-1)] = {
+ .desc = cpu_to_be32(0xd397d781), /* "LpPa" */
+ .size = cpu_to_be16(sizeof(struct lppaca)),
+ .fpregs_in_use = 1,
+ .slb_count = cpu_to_be16(64),
+ .vmxregs_in_use = 0,
+ .page_ins = 0,
+ },
+};
+
+static struct lppaca *extra_lppacas;
+static long __initdata lppaca_size;
+
+static void __init allocate_lppacas(int nr_cpus, unsigned long limit)
+{
+ if (nr_cpus <= NR_LPPACAS)
+ return;
+
+ lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) *
+ (nr_cpus - NR_LPPACAS));
+ extra_lppacas = __va(memblock_alloc_base(lppaca_size,
+ PAGE_SIZE, limit));
+}
+
+static struct lppaca * __init new_lppaca(int cpu)
+{
+ struct lppaca *lp;
+
+ if (cpu < NR_LPPACAS)
+ return &lppaca[cpu];
+
+ lp = extra_lppacas + (cpu - NR_LPPACAS);
+ *lp = lppaca[0];
+
+ return lp;
+}
+
+static void __init free_lppacas(void)
+{
+ long new_size = 0, nr;
+
+ if (!lppaca_size)
+ return;
+ nr = num_possible_cpus() - NR_LPPACAS;
+ if (nr > 0)
+ new_size = PAGE_ALIGN(nr * sizeof(struct lppaca));
+ if (new_size >= lppaca_size)
+ return;
+
+ memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size);
+ lppaca_size = new_size;
+}
+
+#else
+
+static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { }
+static inline void free_lppacas(void) { }
+
+#endif /* CONFIG_PPC_BOOK3S */
+
+#ifdef CONFIG_PPC_STD_MMU_64
+
+/*
+ * 3 persistent SLBs are registered here. The buffer will be zero
+ * initially, hence will all be invaild until we actually write them.
+ *
+ * If you make the number of persistent SLB entries dynamic, please also
+ * update PR KVM to flush and restore them accordingly.
+ */
+static struct slb_shadow *slb_shadow;
+
+static void __init allocate_slb_shadows(int nr_cpus, int limit)
+{
+ int size = PAGE_ALIGN(sizeof(struct slb_shadow) * nr_cpus);
+ slb_shadow = __va(memblock_alloc_base(size, PAGE_SIZE, limit));
+ memset(slb_shadow, 0, size);
+}
+
+static struct slb_shadow * __init init_slb_shadow(int cpu)
+{
+ struct slb_shadow *s = &slb_shadow[cpu];
+
+ /*
+ * When we come through here to initialise boot_paca, the slb_shadow
+ * buffers are not allocated yet. That's OK, we'll get one later in
+ * boot, but make sure we don't corrupt memory at 0.
+ */
+ if (!slb_shadow)
+ return NULL;
+
+ s->persistent = cpu_to_be32(SLB_NUM_BOLTED);
+ s->buffer_length = cpu_to_be32(sizeof(*s));
+
+ return s;
+}
+
+#else /* CONFIG_PPC_STD_MMU_64 */
+
+static void __init allocate_slb_shadows(int nr_cpus, int limit) { }
+
+#endif /* CONFIG_PPC_STD_MMU_64 */
+
+/* The Paca is an array with one entry per processor. Each contains an
+ * lppaca, which contains the information shared between the
+ * hypervisor and Linux.
+ * On systems with hardware multi-threading, there are two threads
+ * per processor. The Paca array must contain an entry for each thread.
+ * The VPD Areas will give a max logical processors = 2 * max physical
+ * processors. The processor VPD array needs one entry per physical
+ * processor (not thread).
+ */
+struct paca_struct *paca;
+EXPORT_SYMBOL(paca);
+
+void __init initialise_paca(struct paca_struct *new_paca, int cpu)
+{
+ /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB
+ * of the TOC can be addressed using a single machine instruction.
+ */
+ unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL;
+
+#ifdef CONFIG_PPC_BOOK3S
+ new_paca->lppaca_ptr = new_lppaca(cpu);
+#else
+ new_paca->kernel_pgd = swapper_pg_dir;
+#endif
+ new_paca->lock_token = 0x8000;
+ new_paca->paca_index = cpu;
+ new_paca->kernel_toc = kernel_toc;
+ new_paca->kernelbase = (unsigned long) _stext;
+ /* Only set MSR:IR/DR when MMU is initialized */
+ new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR);
+ new_paca->hw_cpu_id = 0xffff;
+ new_paca->kexec_state = KEXEC_STATE_NONE;
+ new_paca->__current = &init_task;
+ new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL;
+#ifdef CONFIG_PPC_STD_MMU_64
+ new_paca->slb_shadow_ptr = init_slb_shadow(cpu);
+#endif /* CONFIG_PPC_STD_MMU_64 */
+
+#ifdef CONFIG_PPC_BOOK3E
+ /* For now -- if we have threads this will be adjusted later */
+ new_paca->tcd_ptr = &new_paca->tcd;
+#endif
+}
+
+/* Put the paca pointer into r13 and SPRG_PACA */
+void setup_paca(struct paca_struct *new_paca)
+{
+ /* Setup r13 */
+ local_paca = new_paca;
+
+#ifdef CONFIG_PPC_BOOK3E
+ /* On Book3E, initialize the TLB miss exception frames */
+ mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb);
+#else
+ /* In HV mode, we setup both HPACA and PACA to avoid problems
+ * if we do a GET_PACA() before the feature fixups have been
+ * applied
+ */
+ if (cpu_has_feature(CPU_FTR_HVMODE))
+ mtspr(SPRN_SPRG_HPACA, local_paca);
+#endif
+ mtspr(SPRN_SPRG_PACA, local_paca);
+
+}
+
+static int __initdata paca_size;
+
+void __init allocate_pacas(void)
+{
+ int cpu, limit;
+
+ /*
+ * We can't take SLB misses on the paca, and we want to access them
+ * in real mode, so allocate them within the RMA and also within
+ * the first segment.
+ */
+ limit = min(0x10000000ULL, ppc64_rma_size);
+
+ paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids);
+
+ paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit));
+ memset(paca, 0, paca_size);
+
+ printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n",
+ paca_size, nr_cpu_ids, paca);
+
+ allocate_lppacas(nr_cpu_ids, limit);
+
+ allocate_slb_shadows(nr_cpu_ids, limit);
+
+ /* Can't use for_each_*_cpu, as they aren't functional yet */
+ for (cpu = 0; cpu < nr_cpu_ids; cpu++)
+ initialise_paca(&paca[cpu], cpu);
+}
+
+void __init free_unused_pacas(void)
+{
+ int new_size;
+
+ new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids);
+
+ if (new_size >= paca_size)
+ return;
+
+ memblock_free(__pa(paca) + new_size, paca_size - new_size);
+
+ printk(KERN_DEBUG "Freed %u bytes for unused pacas\n",
+ paca_size - new_size);
+
+ paca_size = new_size;
+
+ free_lppacas();
+}