1 files changed, 717 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/iseries/setup.c b/arch/powerpc/platforms/iseries/setup.c
new file mode 100644
index 00000000000..c25a0815c26
--- /dev/null
+++ b/arch/powerpc/platforms/iseries/setup.c
@@ -0,0 +1,717 @@
+/*
+ *    Copyright (c) 2000 Mike Corrigan <mikejc@us.ibm.com>
+ *    Copyright (c) 1999-2000 Grant Erickson <grant@lcse.umn.edu>
+ *
+ *    Description:
+ *      Architecture- / platform-specific boot-time initialization code for
+ *      the IBM iSeries LPAR.  Adapted from original code by Grant Erickson and
+ *      code by Gary Thomas, Cort Dougan <cort@fsmlabs.com>, and Dan Malek
+ *      <dan@net4x.com>.
+ *
+ *      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.
+ */
+
+#undef DEBUG
+
+#include <linux/init.h>
+#include <linux/threads.h>
+#include <linux/smp.h>
+#include <linux/param.h>
+#include <linux/string.h>
+#include <linux/seq_file.h>
+#include <linux/kdev_t.h>
+#include <linux/kexec.h>
+#include <linux/major.h>
+#include <linux/root_dev.h>
+#include <linux/kernel.h>
+#include <linux/hrtimer.h>
+#include <linux/tick.h>
+
+#include <asm/processor.h>
+#include <asm/machdep.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/pgtable.h>
+#include <asm/mmu_context.h>
+#include <asm/cputable.h>
+#include <asm/sections.h>
+#include <asm/iommu.h>
+#include <asm/firmware.h>
+#include <asm/system.h>
+#include <asm/time.h>
+#include <asm/paca.h>
+#include <asm/cache.h>
+#include <asm/abs_addr.h>
+#include <asm/iseries/hv_lp_config.h>
+#include <asm/iseries/hv_call_event.h>
+#include <asm/iseries/hv_call_xm.h>
+#include <asm/iseries/it_lp_queue.h>
+#include <asm/iseries/mf.h>
+#include <asm/iseries/hv_lp_event.h>
+#include <asm/iseries/lpar_map.h>
+#include <asm/udbg.h>
+#include <asm/irq.h>
+
+#include "naca.h"
+#include "setup.h"
+#include "irq.h"
+#include "vpd_areas.h"
+#include "processor_vpd.h"
+#include "it_lp_naca.h"
+#include "main_store.h"
+#include "call_sm.h"
+#include "call_hpt.h"
+#include "pci.h"
+
+#ifdef DEBUG
+#define DBG(fmt...) udbg_printf(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+/* Function Prototypes */
+static unsigned long build_iSeries_Memory_Map(void);
+static void iseries_shared_idle(void);
+static void iseries_dedicated_idle(void);
+
+
+struct MemoryBlock {
+        unsigned long absStart;
+        unsigned long absEnd;
+        unsigned long logicalStart;
+        unsigned long logicalEnd;
+};
+
+/*
+ * Process the main store vpd to determine where the holes in memory are
+ * and return the number of physical blocks and fill in the array of
+ * block data.
+ */
+static unsigned long iSeries_process_Condor_mainstore_vpd(
+                struct MemoryBlock *mb_array, unsigned long max_entries)
+{
+        unsigned long holeFirstChunk, holeSizeChunks;
+        unsigned long numMemoryBlocks = 1;
+        struct IoHriMainStoreSegment4 *msVpd =
+                (struct IoHriMainStoreSegment4 *)xMsVpd;
+        unsigned long holeStart = msVpd->nonInterleavedBlocksStartAdr;
+        unsigned long holeEnd = msVpd->nonInterleavedBlocksEndAdr;
+        unsigned long holeSize = holeEnd - holeStart;
+
+        printk("Mainstore_VPD: Condor\n");
+        /*
+         * Determine if absolute memory has any
+         * holes so that we can interpret the
+         * access map we get back from the hypervisor
+         * correctly.
+         */
+        mb_array[0].logicalStart = 0;
+        mb_array[0].logicalEnd = 0x100000000UL;
+        mb_array[0].absStart = 0;
+        mb_array[0].absEnd = 0x100000000UL;
+
+        if (holeSize) {
+                numMemoryBlocks = 2;
+                holeStart = holeStart & 0x000fffffffffffffUL;
+                holeStart = addr_to_chunk(holeStart);
+                holeFirstChunk = holeStart;
+                holeSize = addr_to_chunk(holeSize);
+                holeSizeChunks = holeSize;
+                printk( "Main store hole: start chunk = %0lx, size = %0lx chunks\n",
+                                holeFirstChunk, holeSizeChunks );
+                mb_array[0].logicalEnd = holeFirstChunk;
+                mb_array[0].absEnd = holeFirstChunk;
+                mb_array[1].logicalStart = holeFirstChunk;
+                mb_array[1].logicalEnd = 0x100000000UL - holeSizeChunks;
+                mb_array[1].absStart = holeFirstChunk + holeSizeChunks;
+                mb_array[1].absEnd = 0x100000000UL;
+        }
+        return numMemoryBlocks;
+}
+
+#define MaxSegmentAreas                 32
+#define MaxSegmentAdrRangeBlocks        128
+#define MaxAreaRangeBlocks              4
+
+static unsigned long iSeries_process_Regatta_mainstore_vpd(
+                struct MemoryBlock *mb_array, unsigned long max_entries)
+{
+        struct IoHriMainStoreSegment5 *msVpdP =
+                (struct IoHriMainStoreSegment5 *)xMsVpd;
+        unsigned long numSegmentBlocks = 0;
+        u32 existsBits = msVpdP->msAreaExists;
+        unsigned long area_num;
+
+        printk("Mainstore_VPD: Regatta\n");
+
+        for (area_num = 0; area_num < MaxSegmentAreas; ++area_num ) {
+                unsigned long numAreaBlocks;
+                struct IoHriMainStoreArea4 *currentArea;
+
+                if (existsBits & 0x80000000) {
+                        unsigned long block_num;
+
+                        currentArea = &msVpdP->msAreaArray[area_num];
+                        numAreaBlocks = currentArea->numAdrRangeBlocks;
+                        printk("ms_vpd: processing area %2ld  blocks=%ld",
+                                        area_num, numAreaBlocks);
+                        for (block_num = 0; block_num < numAreaBlocks;
+                                        ++block_num ) {
+                                /* Process an address range block */
+                                struct MemoryBlock tempBlock;
+                                unsigned long i;
+
+                                tempBlock.absStart =
+                                        (unsigned long)currentArea->xAdrRangeBlock[block_num].blockStart;
+                                tempBlock.absEnd =
+                                        (unsigned long)currentArea->xAdrRangeBlock[block_num].blockEnd;
+                                tempBlock.logicalStart = 0;
+                                tempBlock.logicalEnd   = 0;
+                                printk("\n          block %ld absStart=%016lx absEnd=%016lx",
+                                                block_num, tempBlock.absStart,
+                                                tempBlock.absEnd);
+
+                                for (i = 0; i < numSegmentBlocks; ++i) {
+                                        if (mb_array[i].absStart ==
+                                                        tempBlock.absStart)
+                                                break;
+                                }
+                                if (i == numSegmentBlocks) {
+                                        if (numSegmentBlocks == max_entries)
+                                                panic("iSeries_process_mainstore_vpd: too many memory blocks");
+                                        mb_array[numSegmentBlocks] = tempBlock;
+                                        ++numSegmentBlocks;
+                                } else
+                                        printk(" (duplicate)");
+                        }
+                        printk("\n");
+                }
+                existsBits <<= 1;
+        }
+        /* Now sort the blocks found into ascending sequence */
+        if (numSegmentBlocks > 1) {
+                unsigned long m, n;
+
+                for (m = 0; m < numSegmentBlocks - 1; ++m) {
+                        for (n = numSegmentBlocks - 1; m < n; --n) {
+                                if (mb_array[n].absStart <
+                                                mb_array[n-1].absStart) {
+                                        struct MemoryBlock tempBlock;
+
+                                        tempBlock = mb_array[n];
+                                        mb_array[n] = mb_array[n-1];
+                                        mb_array[n-1] = tempBlock;
+                                }
+                        }
+                }
+        }
+        /*
+         * Assign "logical" addresses to each block.  These
+         * addresses correspond to the hypervisor "bitmap" space.
+         * Convert all addresses into units of 256K chunks.
+         */
+        {
+        unsigned long i, nextBitmapAddress;
+
+        printk("ms_vpd: %ld sorted memory blocks\n", numSegmentBlocks);
+        nextBitmapAddress = 0;
+        for (i = 0; i < numSegmentBlocks; ++i) {
+                unsigned long length = mb_array[i].absEnd -
+                        mb_array[i].absStart;
+
+                mb_array[i].logicalStart = nextBitmapAddress;
+                mb_array[i].logicalEnd = nextBitmapAddress + length;
+                nextBitmapAddress += length;
+                printk("          Bitmap range: %016lx - %016lx\n"
+                                "        Absolute range: %016lx - %016lx\n",
+                                mb_array[i].logicalStart,
+                                mb_array[i].logicalEnd,
+                                mb_array[i].absStart, mb_array[i].absEnd);
+                mb_array[i].absStart = addr_to_chunk(mb_array[i].absStart &
+                                0x000fffffffffffffUL);
+                mb_array[i].absEnd = addr_to_chunk(mb_array[i].absEnd &
+                                0x000fffffffffffffUL);
+                mb_array[i].logicalStart =
+                        addr_to_chunk(mb_array[i].logicalStart);
+                mb_array[i].logicalEnd = addr_to_chunk(mb_array[i].logicalEnd);
+        }
+        }
+
+        return numSegmentBlocks;
+}
+
+static unsigned long iSeries_process_mainstore_vpd(struct MemoryBlock *mb_array,
+                unsigned long max_entries)
+{
+        unsigned long i;
+        unsigned long mem_blocks = 0;
+
+        if (mmu_has_feature(MMU_FTR_SLB))
+                mem_blocks = iSeries_process_Regatta_mainstore_vpd(mb_array,
+                                max_entries);
+        else
+                mem_blocks = iSeries_process_Condor_mainstore_vpd(mb_array,
+                                max_entries);
+
+        printk("Mainstore_VPD: numMemoryBlocks = %ld\n", mem_blocks);
+        for (i = 0; i < mem_blocks; ++i) {
+                printk("Mainstore_VPD: block %3ld logical chunks %016lx - %016lx\n"
+                       "                             abs chunks %016lx - %016lx\n",
+                        i, mb_array[i].logicalStart, mb_array[i].logicalEnd,
+                        mb_array[i].absStart, mb_array[i].absEnd);
+        }
+        return mem_blocks;
+}
+
+static void __init iSeries_get_cmdline(void)
+{
+        char *p, *q;
+
+        /* copy the command line parameter from the primary VSP  */
+        HvCallEvent_dmaToSp(cmd_line, 2 * 64* 1024, 256,
+                        HvLpDma_Direction_RemoteToLocal);
+
+        p = cmd_line;
+        q = cmd_line + 255;
+        while(p < q) {
+                if (!*p || *p == '\n')
+                        break;
+                ++p;
+        }
+        *p = 0;
+}
+
+static void __init iSeries_init_early(void)
+{
+        DBG(" -> iSeries_init_early()\n");
+
+        /* Snapshot the timebase, for use in later recalibration */
+        iSeries_time_init_early();
+
+        /*
+         * Initialize the DMA/TCE management
+         */
+        iommu_init_early_iSeries();
+
+        /* Initialize machine-dependency vectors */
+#ifdef CONFIG_SMP
+        smp_init_iSeries();
+#endif
+
+        /* Associate Lp Event Queue 0 with processor 0 */
+        HvCallEvent_setLpEventQueueInterruptProc(0, 0);
+
+        mf_init();
+
+        DBG(" <- iSeries_init_early()\n");
+}
+
+struct mschunks_map mschunks_map = {
+        /* XXX We don't use these, but Piranha might need them. */
+        .chunk_size  = MSCHUNKS_CHUNK_SIZE,
+        .chunk_shift = MSCHUNKS_CHUNK_SHIFT,
+        .chunk_mask  = MSCHUNKS_OFFSET_MASK,
+};
+EXPORT_SYMBOL(mschunks_map);
+
+static void mschunks_alloc(unsigned long num_chunks)
+{
+        klimit = _ALIGN(klimit, sizeof(u32));
+        mschunks_map.mapping = (u32 *)klimit;
+        klimit += num_chunks * sizeof(u32);
+        mschunks_map.num_chunks = num_chunks;
+}
+
+/*
+ * The iSeries may have very large memories ( > 128 GB ) and a partition
+ * may get memory in "chunks" that may be anywhere in the 2**52 real
+ * address space.  The chunks are 256K in size.  To map this to the
+ * memory model Linux expects, the AS/400 specific code builds a
+ * translation table to translate what Linux thinks are "physical"
+ * addresses to the actual real addresses.  This allows us to make
+ * it appear to Linux that we have contiguous memory starting at
+ * physical address zero while in fact this could be far from the truth.
+ * To avoid confusion, I'll let the words physical and/or real address
+ * apply to the Linux addresses while I'll use "absolute address" to
+ * refer to the actual hardware real address.
+ *
+ * build_iSeries_Memory_Map gets information from the Hypervisor and
+ * looks at the Main Store VPD to determine the absolute addresses
+ * of the memory that has been assigned to our partition and builds
+ * a table used to translate Linux's physical addresses to these
+ * absolute addresses.  Absolute addresses are needed when
+ * communicating with the hypervisor (e.g. to build HPT entries)
+ *
+ * Returns the physical memory size
+ */
+
+static unsigned long __init build_iSeries_Memory_Map(void)
+{
+        u32 loadAreaFirstChunk, loadAreaLastChunk, loadAreaSize;
+        u32 nextPhysChunk;
+        u32 hptFirstChunk, hptLastChunk, hptSizeChunks, hptSizePages;
+        u32 totalChunks,moreChunks;
+        u32 currChunk, thisChunk, absChunk;
+        u32 currDword;
+        u32 chunkBit;
+        u64 map;
+        struct MemoryBlock mb[32];
+        unsigned long numMemoryBlocks, curBlock;
+
+        /* Chunk size on iSeries is 256K bytes */
+        totalChunks = (u32)HvLpConfig_getMsChunks();
+        mschunks_alloc(totalChunks);
+
+        /*
+         * Get absolute address of our load area
+         * and map it to physical address 0
+         * This guarantees that the loadarea ends up at physical 0
+         * otherwise, it might not be returned by PLIC as the first
+         * chunks
+         */
+
+        loadAreaFirstChunk = (u32)addr_to_chunk(itLpNaca.xLoadAreaAddr);
+        loadAreaSize =  itLpNaca.xLoadAreaChunks;
+
+        /*
+         * Only add the pages already mapped here.
+         * Otherwise we might add the hpt pages
+         * The rest of the pages of the load area
+         * aren't in the HPT yet and can still
+         * be assigned an arbitrary physical address
+         */
+        if ((loadAreaSize * 64) > HvPagesToMap)
+                loadAreaSize = HvPagesToMap / 64;
+
+        loadAreaLastChunk = loadAreaFirstChunk + loadAreaSize - 1;
+
+        /*
+         * TODO Do we need to do something if the HPT is in the 64MB load area?
+         * This would be required if the itLpNaca.xLoadAreaChunks includes
+         * the HPT size
+         */
+
+        printk("Mapping load area - physical addr = 0000000000000000\n"
+                "                    absolute addr = %016lx\n",
+                chunk_to_addr(loadAreaFirstChunk));
+        printk("Load area size %dK\n", loadAreaSize * 256);
+
+        for (nextPhysChunk = 0; nextPhysChunk < loadAreaSize; ++nextPhysChunk)
+                mschunks_map.mapping[nextPhysChunk] =
+                        loadAreaFirstChunk + nextPhysChunk;
+
+        /*
+         * Get absolute address of our HPT and remember it so
+         * we won't map it to any physical address
+         */
+        hptFirstChunk = (u32)addr_to_chunk(HvCallHpt_getHptAddress());
+        hptSizePages = (u32)HvCallHpt_getHptPages();
+        hptSizeChunks = hptSizePages >>
+                (MSCHUNKS_CHUNK_SHIFT - HW_PAGE_SHIFT);
+        hptLastChunk = hptFirstChunk + hptSizeChunks - 1;
+
+        printk("HPT absolute addr = %016lx, size = %dK\n",
+                        chunk_to_addr(hptFirstChunk), hptSizeChunks * 256);
+
+        /*
+         * Determine if absolute memory has any
+         * holes so that we can interpret the
+         * access map we get back from the hypervisor
+         * correctly.
+         */
+        numMemoryBlocks = iSeries_process_mainstore_vpd(mb, 32);
+
+        /*
+         * Process the main store access map from the hypervisor
+         * to build up our physical -> absolute translation table
+         */
+        curBlock = 0;
+        currChunk = 0;
+        currDword = 0;
+        moreChunks = totalChunks;
+
+        while (moreChunks) {
+                map = HvCallSm_get64BitsOfAccessMap(itLpNaca.xLpIndex,
+                                currDword);
+                thisChunk = currChunk;
+                while (map) {
+                        chunkBit = map >> 63;
+                        map <<= 1;
+                        if (chunkBit) {
+                                --moreChunks;
+                                while (thisChunk >= mb[curBlock].logicalEnd) {
+                                        ++curBlock;
+                                        if (curBlock >= numMemoryBlocks)
+                                                panic("out of memory blocks");
+                                }
+                                if (thisChunk < mb[curBlock].logicalStart)
+                                        panic("memory block error");
+
+                                absChunk = mb[curBlock].absStart +
+                                        (thisChunk - mb[curBlock].logicalStart);
+                                if (((absChunk < hptFirstChunk) ||
+                                     (absChunk > hptLastChunk)) &&
+                                    ((absChunk < loadAreaFirstChunk) ||
+                                     (absChunk > loadAreaLastChunk))) {
+                                        mschunks_map.mapping[nextPhysChunk] =
+                                                absChunk;
+                                        ++nextPhysChunk;
+                                }
+                        }
+                        ++thisChunk;
+                }
+                ++currDword;
+                currChunk += 64;
+        }
+
+        /*
+         * main store size (in chunks) is
+         *   totalChunks - hptSizeChunks
+         * which should be equal to
+         *   nextPhysChunk
+         */
+        return chunk_to_addr(nextPhysChunk);
+}
+
+/*
+ * Document me.
+ */
+static void __init iSeries_setup_arch(void)
+{
+        if (get_lppaca()->shared_proc) {
+                ppc_md.idle_loop = iseries_shared_idle;
+                printk(KERN_DEBUG "Using shared processor idle loop\n");
+        } else {
+                ppc_md.idle_loop = iseries_dedicated_idle;
+                printk(KERN_DEBUG "Using dedicated idle loop\n");
+        }
+
+        /* Setup the Lp Event Queue */
+        setup_hvlpevent_queue();
+
+        printk("Max  logical processors = %d\n",
+                        itVpdAreas.xSlicMaxLogicalProcs);
+        printk("Max physical processors = %d\n",
+                        itVpdAreas.xSlicMaxPhysicalProcs);
+
+        iSeries_pcibios_init();
+}
+
+static void iSeries_show_cpuinfo(struct seq_file *m)
+{
+        seq_printf(m, "machine\t\t: 64-bit iSeries Logical Partition\n");
+}
+
+static void __init iSeries_progress(char * st, unsigned short code)
+{
+        printk("Progress: [%04x] - %s\n", (unsigned)code, st);
+        mf_display_progress(code);
+}
+
+static void __init iSeries_fixup_klimit(void)
+{
+        /*
+         * Change klimit to take into account any ram disk
+         * that may be included
+         */
+        if (naca.xRamDisk)
+                klimit = KERNELBASE + (u64)naca.xRamDisk +
+                        (naca.xRamDiskSize * HW_PAGE_SIZE);
+}
+
+static int __init iSeries_src_init(void)
+{
+        /* clear the progress line */
+        if (firmware_has_feature(FW_FEATURE_ISERIES))
+                ppc_md.progress(" ", 0xffff);
+        return 0;
+}
+
+late_initcall(iSeries_src_init);
+
+static inline void process_iSeries_events(void)
+{
+        asm volatile ("li 0,0x5555; sc" : : : "r0", "r3");
+}
+
+static void yield_shared_processor(void)
+{
+        unsigned long tb;
+
+        HvCall_setEnabledInterrupts(HvCall_MaskIPI |
+                                    HvCall_MaskLpEvent |
+                                    HvCall_MaskLpProd |
+                                    HvCall_MaskTimeout);
+
+        tb = get_tb();
+        /* Compute future tb value when yield should expire */
+        HvCall_yieldProcessor(HvCall_YieldTimed, tb+tb_ticks_per_jiffy);
+
+        /*
+         * The decrementer stops during the yield.  Force a fake decrementer
+         * here and let the timer_interrupt code sort out the actual time.
+         */
+        get_lppaca()->int_dword.fields.decr_int = 1;
+        ppc64_runlatch_on();
+        process_iSeries_events();
+}
+
+static void iseries_shared_idle(void)
+{
+        while (1) {
+                tick_nohz_stop_sched_tick(1);
+                while (!need_resched() && !hvlpevent_is_pending()) {
+                        local_irq_disable();
+                        ppc64_runlatch_off();
+
+                        /* Recheck with irqs off */
+                        if (!need_resched() && !hvlpevent_is_pending())
+                                yield_shared_processor();
+
+                        HMT_medium();
+                        local_irq_enable();
+                }
+
+                ppc64_runlatch_on();
+                tick_nohz_restart_sched_tick();
+
+                if (hvlpevent_is_pending())
+                        process_iSeries_events();
+
+                preempt_enable_no_resched();
+                schedule();
+                preempt_disable();
+        }
+}
+
+static void iseries_dedicated_idle(void)
+{
+        set_thread_flag(TIF_POLLING_NRFLAG);
+
+        while (1) {
+                tick_nohz_stop_sched_tick(1);
+                if (!need_resched()) {
+                        while (!need_resched()) {
+                                ppc64_runlatch_off();
+                                HMT_low();
+
+                                if (hvlpevent_is_pending()) {
+                                        HMT_medium();
+                                        ppc64_runlatch_on();
+                                        process_iSeries_events();
+                                }
+                        }
+
+                        HMT_medium();
+                }
+
+                ppc64_runlatch_on();
+                tick_nohz_restart_sched_tick();
+                preempt_enable_no_resched();
+                schedule();
+                preempt_disable();
+        }
+}
+
+static void __iomem *iseries_ioremap(phys_addr_t address, unsigned long size,
+                                     unsigned long flags, void *caller)
+{
+        return (void __iomem *)address;
+}
+
+static void iseries_iounmap(volatile void __iomem *token)
+{
+}
+
+static int __init iseries_probe(void)
+{
+        unsigned long root = of_get_flat_dt_root();
+        if (!of_flat_dt_is_compatible(root, "IBM,iSeries"))
+                return 0;
+
+        hpte_init_iSeries();
+        /* iSeries does not support 16M pages */
+        cur_cpu_spec->mmu_features &= ~MMU_FTR_16M_PAGE;
+
+        return 1;
+}
+
+#ifdef CONFIG_KEXEC
+static int iseries_kexec_prepare(struct kimage *image)
+{
+        return -ENOSYS;
+}
+#endif
+
+define_machine(iseries) {
+        .name                   = "iSeries",
+        .setup_arch             = iSeries_setup_arch,
+        .show_cpuinfo           = iSeries_show_cpuinfo,
+        .init_IRQ               = iSeries_init_IRQ,
+        .get_irq                = iSeries_get_irq,
+        .init_early             = iSeries_init_early,
+        .pcibios_fixup          = iSeries_pci_final_fixup,
+        .pcibios_fixup_resources= iSeries_pcibios_fixup_resources,
+        .restart                = mf_reboot,
+        .power_off              = mf_power_off,
+        .halt                   = mf_power_off,
+        .get_boot_time          = iSeries_get_boot_time,
+        .set_rtc_time           = iSeries_set_rtc_time,
+        .get_rtc_time           = iSeries_get_rtc_time,
+        .calibrate_decr         = generic_calibrate_decr,
+        .progress               = iSeries_progress,
+        .probe                  = iseries_probe,
+        .ioremap                = iseries_ioremap,
+        .iounmap                = iseries_iounmap,
+#ifdef CONFIG_KEXEC
+        .machine_kexec_prepare  = iseries_kexec_prepare,
+#endif
+        /* XXX Implement enable_pmcs for iSeries */
+};
+
+void * __init iSeries_early_setup(void)
+{
+        unsigned long phys_mem_size;
+
+        /* Identify CPU type. This is done again by the common code later
+         * on but calling this function multiple times is fine.
+         */
+        identify_cpu(0, mfspr(SPRN_PVR));
+        initialise_paca(&boot_paca, 0);
+
+        powerpc_firmware_features |= FW_FEATURE_ISERIES;
+        powerpc_firmware_features |= FW_FEATURE_LPAR;
+
+#ifdef CONFIG_SMP
+        /* On iSeries we know we can never have more than 64 cpus */
+        nr_cpu_ids = max(nr_cpu_ids, 64);
+#endif
+
+        iSeries_fixup_klimit();
+
+        /*
+         * Initialize the table which translate Linux physical addresses to
+         * AS/400 absolute addresses
+         */
+        phys_mem_size = build_iSeries_Memory_Map();
+
+        iSeries_get_cmdline();
+
+        return (void *) __pa(build_flat_dt(phys_mem_size));
+}
+
+static void hvputc(char c)
+{
+        if (c == '\n')
+                hvputc('\r');
+
+        HvCall_writeLogBuffer(&c, 1);
+}
+
+void __init udbg_init_iseries(void)
+{
+        udbg_putc = hvputc;
+}