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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-08 09:31:42 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-08 09:31:42 -0800
commitdde0013782dbd09e1cc68ca03860f3a62b03cb34 (patch)
tree5be40012944c0fab834a385f2410eaa60e2b0d6e
parentf3aafa6c2535d36542a6dfc8647cd2fdb5999648 (diff)
parenta99824f327c748b2753f4fa570eb1fefcd6a9c4d (diff)
Merge branch 'for-2.6.25' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'for-2.6.25' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: [POWERPC] Add arch-specific walk_memory_remove() for 64-bit powerpc [POWERPC] Enable hotplug memory remove for 64-bit powerpc [POWERPC] Add remove_memory() for 64-bit powerpc [POWERPC] Make cell IOMMU fixed mapping printk more useful [POWERPC] Fix potential cell IOMMU bug when switching back to default DMA ops [POWERPC] Don't enable cell IOMMU fixed mapping if there are no dma-ranges [POWERPC] Fix cell IOMMU null pointer explosion on old firmwares [POWERPC] spufs: Fix timing dependent false return from spufs_run_spu [POWERPC] spufs: No need to have a runnable SPU for libassist update [POWERPC] spufs: Update SPU_Status[CISHP] in backing runcntl write [POWERPC] spufs: Fix state_mutex leaks [POWERPC] Disable G5 NAP mode during SMU commands on U3
-rw-r--r--arch/powerpc/Kconfig6
-rw-r--r--arch/powerpc/mm/mem.c33
-rw-r--r--arch/powerpc/platforms/cell/iommu.c48
-rw-r--r--arch/powerpc/platforms/cell/spufs/backing_ops.c6
-rw-r--r--arch/powerpc/platforms/cell/spufs/fault.c12
-rw-r--r--arch/powerpc/platforms/cell/spufs/file.c49
-rw-r--r--arch/powerpc/platforms/cell/spufs/run.c21
-rw-r--r--arch/powerpc/platforms/cell/spufs/spufs.h5
-rw-r--r--arch/powerpc/platforms/powermac/feature.c11
-rw-r--r--drivers/macintosh/smu.c25
-rw-r--r--include/asm-powerpc/pmac_feature.h8
-rw-r--r--kernel/resource.c2
12 files changed, 166 insertions, 60 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 8dcac0b22d6..26b963c33c8 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -272,6 +272,12 @@ config HOTPLUG_CPU
config ARCH_ENABLE_MEMORY_HOTPLUG
def_bool y
+config ARCH_HAS_WALK_MEMORY
+ def_bool y
+
+config ARCH_ENABLE_MEMORY_HOTREMOVE
+ def_bool y
+
config KEXEC
bool "kexec system call (EXPERIMENTAL)"
depends on (PPC_PRPMC2800 || PPC_MULTIPLATFORM) && EXPERIMENTAL
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 93a5c53e342..be5c506779a 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -129,6 +129,39 @@ int __devinit arch_add_memory(int nid, u64 start, u64 size)
return __add_pages(zone, start_pfn, nr_pages);
}
+#ifdef CONFIG_MEMORY_HOTREMOVE
+int remove_memory(u64 start, u64 size)
+{
+ unsigned long start_pfn, end_pfn;
+ int ret;
+
+ start_pfn = start >> PAGE_SHIFT;
+ end_pfn = start_pfn + (size >> PAGE_SHIFT);
+ ret = offline_pages(start_pfn, end_pfn, 120 * HZ);
+ if (ret)
+ goto out;
+ /* Arch-specific calls go here - next patch */
+out:
+ return ret;
+}
+#endif /* CONFIG_MEMORY_HOTREMOVE */
+
+/*
+ * walk_memory_resource() needs to make sure there is no holes in a given
+ * memory range. On PPC64, since this range comes from /sysfs, the range
+ * is guaranteed to be valid, non-overlapping and can not contain any
+ * holes. By the time we get here (memory add or remove), /proc/device-tree
+ * is updated and correct. Only reason we need to check against device-tree
+ * would be if we allow user-land to specify a memory range through a
+ * system call/ioctl etc. instead of doing offline/online through /sysfs.
+ */
+int
+walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
+ int (*func)(unsigned long, unsigned long, void *))
+{
+ return (*func)(start_pfn, nr_pages, arg);
+}
+
#endif /* CONFIG_MEMORY_HOTPLUG */
void show_mem(void)
diff --git a/arch/powerpc/platforms/cell/iommu.c b/arch/powerpc/platforms/cell/iommu.c
index df330666ccc..edab631a8dc 100644
--- a/arch/powerpc/platforms/cell/iommu.c
+++ b/arch/powerpc/platforms/cell/iommu.c
@@ -26,6 +26,7 @@
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
+#include <linux/of.h>
#include <linux/of_platform.h>
#include <asm/prom.h>
@@ -789,18 +790,16 @@ static int __init cell_iommu_init_disabled(void)
static u64 cell_iommu_get_fixed_address(struct device *dev)
{
u64 cpu_addr, size, best_size, pci_addr = OF_BAD_ADDR;
- struct device_node *tmp, *np;
+ struct device_node *np;
const u32 *ranges = NULL;
int i, len, best;
- np = dev->archdata.of_node;
- of_node_get(np);
- ranges = of_get_property(np, "dma-ranges", &len);
- while (!ranges && np) {
- tmp = of_get_parent(np);
- of_node_put(np);
- np = tmp;
+ np = of_node_get(dev->archdata.of_node);
+ while (np) {
ranges = of_get_property(np, "dma-ranges", &len);
+ if (ranges)
+ break;
+ np = of_get_next_parent(np);
}
if (!ranges) {
@@ -842,19 +841,18 @@ static int dma_set_mask_and_switch(struct device *dev, u64 dma_mask)
if (!dev->dma_mask || !dma_supported(dev, dma_mask))
return -EIO;
- if (dma_mask == DMA_BIT_MASK(64)) {
- if (cell_iommu_get_fixed_address(dev) == OF_BAD_ADDR)
- dev_dbg(dev, "iommu: 64-bit OK, but bad addr\n");
- else {
- dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n");
- set_dma_ops(dev, &dma_iommu_fixed_ops);
- cell_dma_dev_setup(dev);
- }
+ if (dma_mask == DMA_BIT_MASK(64) &&
+ cell_iommu_get_fixed_address(dev) != OF_BAD_ADDR)
+ {
+ dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n");
+ set_dma_ops(dev, &dma_iommu_fixed_ops);
} else {
dev_dbg(dev, "iommu: not 64-bit, using default ops\n");
set_dma_ops(dev, get_pci_dma_ops());
}
+ cell_dma_dev_setup(dev);
+
*dev->dma_mask = dma_mask;
return 0;
@@ -918,6 +916,18 @@ static int __init cell_iommu_fixed_mapping_init(void)
return -1;
}
+ /* We must have dma-ranges properties for fixed mapping to work */
+ for (np = NULL; (np = of_find_all_nodes(np));) {
+ if (of_find_property(np, "dma-ranges", NULL))
+ break;
+ }
+ of_node_put(np);
+
+ if (!np) {
+ pr_debug("iommu: no dma-ranges found, no fixed mapping\n");
+ return -1;
+ }
+
/* The default setup is to have the fixed mapping sit after the
* dynamic region, so find the top of the largest IOMMU window
* on any axon, then add the size of RAM and that's our max value.
@@ -981,8 +991,8 @@ static int __init cell_iommu_fixed_mapping_init(void)
dsize = htab_size_bytes;
}
- pr_debug("iommu: setting up %d, dynamic window %lx-%lx " \
- "fixed window %lx-%lx\n", iommu->nid, dbase,
+ printk(KERN_DEBUG "iommu: node %d, dynamic window 0x%lx-0x%lx "
+ "fixed window 0x%lx-0x%lx\n", iommu->nid, dbase,
dbase + dsize, fbase, fbase + fsize);
cell_iommu_setup_page_tables(iommu, dbase, dsize, fbase, fsize);
@@ -998,8 +1008,6 @@ static int __init cell_iommu_fixed_mapping_init(void)
dma_iommu_ops.set_dma_mask = dma_set_mask_and_switch;
set_pci_dma_ops(&dma_iommu_ops);
- printk(KERN_DEBUG "IOMMU fixed mapping established.\n");
-
return 0;
}
diff --git a/arch/powerpc/platforms/cell/spufs/backing_ops.c b/arch/powerpc/platforms/cell/spufs/backing_ops.c
index 50d98a154aa..64eb15b2204 100644
--- a/arch/powerpc/platforms/cell/spufs/backing_ops.c
+++ b/arch/powerpc/platforms/cell/spufs/backing_ops.c
@@ -288,6 +288,12 @@ static void spu_backing_runcntl_write(struct spu_context *ctx, u32 val)
spin_lock(&ctx->csa.register_lock);
ctx->csa.prob.spu_runcntl_RW = val;
if (val & SPU_RUNCNTL_RUNNABLE) {
+ ctx->csa.prob.spu_status_R &=
+ ~SPU_STATUS_STOPPED_BY_STOP &
+ ~SPU_STATUS_STOPPED_BY_HALT &
+ ~SPU_STATUS_SINGLE_STEP &
+ ~SPU_STATUS_INVALID_INSTR &
+ ~SPU_STATUS_INVALID_CH;
ctx->csa.prob.spu_status_R |= SPU_STATUS_RUNNING;
} else {
ctx->csa.prob.spu_status_R &= ~SPU_STATUS_RUNNING;
diff --git a/arch/powerpc/platforms/cell/spufs/fault.c b/arch/powerpc/platforms/cell/spufs/fault.c
index eff4d291ba8..e46d300e21a 100644
--- a/arch/powerpc/platforms/cell/spufs/fault.c
+++ b/arch/powerpc/platforms/cell/spufs/fault.c
@@ -108,7 +108,7 @@ int spufs_handle_class1(struct spu_context *ctx)
u64 ea, dsisr, access;
unsigned long flags;
unsigned flt = 0;
- int ret, ret2;
+ int ret;
/*
* dar and dsisr get passed from the registers
@@ -148,13 +148,10 @@ int spufs_handle_class1(struct spu_context *ctx)
ret = spu_handle_mm_fault(current->mm, ea, dsisr, &flt);
/*
- * If spu_acquire fails due to a pending signal we just want to return
- * EINTR to userspace even if that means missing the dma restart or
- * updating the page fault statistics.
+ * This is nasty: we need the state_mutex for all the bookkeeping even
+ * if the syscall was interrupted by a signal. ewww.
*/
- ret2 = spu_acquire(ctx);
- if (ret2)
- goto out;
+ mutex_lock(&ctx->state_mutex);
/*
* Clear dsisr under ctxt lock after handling the fault, so that
@@ -185,7 +182,6 @@ int spufs_handle_class1(struct spu_context *ctx)
} else
spufs_handle_event(ctx, ea, SPE_EVENT_SPE_DATA_STORAGE);
- out:
spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
return ret;
}
diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c
index e393144d533..c66c3756970 100644
--- a/arch/powerpc/platforms/cell/spufs/file.c
+++ b/arch/powerpc/platforms/cell/spufs/file.c
@@ -358,6 +358,7 @@ static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
{
struct spu_context *ctx = vma->vm_file->private_data;
unsigned long area, offset = address - vma->vm_start;
+ int ret = 0;
spu_context_nospu_trace(spufs_ps_nopfn__enter, ctx);
@@ -379,7 +380,7 @@ static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
if (ctx->state == SPU_STATE_SAVED) {
up_read(&current->mm->mmap_sem);
spu_context_nospu_trace(spufs_ps_nopfn__sleep, ctx);
- spufs_wait(ctx->run_wq, ctx->state == SPU_STATE_RUNNABLE);
+ ret = spufs_wait(ctx->run_wq, ctx->state == SPU_STATE_RUNNABLE);
spu_context_trace(spufs_ps_nopfn__wake, ctx, ctx->spu);
down_read(&current->mm->mmap_sem);
} else {
@@ -388,7 +389,8 @@ static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
spu_context_trace(spufs_ps_nopfn__insert, ctx, ctx->spu);
}
- spu_release(ctx);
+ if (!ret)
+ spu_release(ctx);
return NOPFN_REFAULT;
}
@@ -755,23 +757,25 @@ static ssize_t spufs_ibox_read(struct file *file, char __user *buf,
count = spu_acquire(ctx);
if (count)
- return count;
+ goto out;
/* wait only for the first element */
count = 0;
if (file->f_flags & O_NONBLOCK) {
- if (!spu_ibox_read(ctx, &ibox_data))
+ if (!spu_ibox_read(ctx, &ibox_data)) {
count = -EAGAIN;
+ goto out_unlock;
+ }
} else {
count = spufs_wait(ctx->ibox_wq, spu_ibox_read(ctx, &ibox_data));
+ if (count)
+ goto out;
}
- if (count)
- goto out;
/* if we can't write at all, return -EFAULT */
count = __put_user(ibox_data, udata);
if (count)
- goto out;
+ goto out_unlock;
for (count = 4, udata++; (count + 4) <= len; count += 4, udata++) {
int ret;
@@ -788,9 +792,9 @@ static ssize_t spufs_ibox_read(struct file *file, char __user *buf,
break;
}
-out:
+out_unlock:
spu_release(ctx);
-
+out:
return count;
}
@@ -905,7 +909,7 @@ static ssize_t spufs_wbox_write(struct file *file, const char __user *buf,
count = spu_acquire(ctx);
if (count)
- return count;
+ goto out;
/*
* make sure we can at least write one element, by waiting
@@ -913,14 +917,16 @@ static ssize_t spufs_wbox_write(struct file *file, const char __user *buf,
*/
count = 0;
if (file->f_flags & O_NONBLOCK) {
- if (!spu_wbox_write(ctx, wbox_data))
+ if (!spu_wbox_write(ctx, wbox_data)) {
count = -EAGAIN;
+ goto out_unlock;
+ }
} else {
count = spufs_wait(ctx->wbox_wq, spu_wbox_write(ctx, wbox_data));
+ if (count)
+ goto out;
}
- if (count)
- goto out;
/* write as much as possible */
for (count = 4, udata++; (count + 4) <= len; count += 4, udata++) {
@@ -934,8 +940,9 @@ static ssize_t spufs_wbox_write(struct file *file, const char __user *buf,
break;
}
-out:
+out_unlock:
spu_release(ctx);
+out:
return count;
}
@@ -1598,12 +1605,11 @@ static ssize_t spufs_mfc_read(struct file *file, char __user *buffer,
} else {
ret = spufs_wait(ctx->mfc_wq,
spufs_read_mfc_tagstatus(ctx, &status));
+ if (ret)
+ goto out;
}
spu_release(ctx);
- if (ret)
- goto out;
-
ret = 4;
if (copy_to_user(buffer, &status, 4))
ret = -EFAULT;
@@ -1732,6 +1738,8 @@ static ssize_t spufs_mfc_write(struct file *file, const char __user *buffer,
int status;
ret = spufs_wait(ctx->mfc_wq,
spu_send_mfc_command(ctx, cmd, &status));
+ if (ret)
+ goto out;
if (status)
ret = status;
}
@@ -1785,7 +1793,7 @@ static int spufs_mfc_flush(struct file *file, fl_owner_t id)
ret = spu_acquire(ctx);
if (ret)
- return ret;
+ goto out;
#if 0
/* this currently hangs */
ret = spufs_wait(ctx->mfc_wq,
@@ -1794,12 +1802,13 @@ static int spufs_mfc_flush(struct file *file, fl_owner_t id)
goto out;
ret = spufs_wait(ctx->mfc_wq,
ctx->ops->read_mfc_tagstatus(ctx) == ctx->tagwait);
-out:
+ if (ret)
+ goto out;
#else
ret = 0;
#endif
spu_release(ctx);
-
+out:
return ret;
}
diff --git a/arch/powerpc/platforms/cell/spufs/run.c b/arch/powerpc/platforms/cell/spufs/run.c
index b4814c740d8..fca22e18069 100644
--- a/arch/powerpc/platforms/cell/spufs/run.c
+++ b/arch/powerpc/platforms/cell/spufs/run.c
@@ -53,7 +53,7 @@ int spu_stopped(struct spu_context *ctx, u32 *stat)
stopped = SPU_STATUS_INVALID_INSTR | SPU_STATUS_SINGLE_STEP |
SPU_STATUS_STOPPED_BY_HALT | SPU_STATUS_STOPPED_BY_STOP;
- if (*stat & stopped)
+ if (!(*stat & SPU_STATUS_RUNNING) && (*stat & stopped))
return 1;
dsisr = ctx->csa.dsisr;
@@ -354,8 +354,15 @@ long spufs_run_spu(struct spu_context *ctx, u32 *npc, u32 *event)
do {
ret = spufs_wait(ctx->stop_wq, spu_stopped(ctx, &status));
- if (unlikely(ret))
+ if (unlikely(ret)) {
+ /*
+ * This is nasty: we need the state_mutex for all the
+ * bookkeeping even if the syscall was interrupted by
+ * a signal. ewww.
+ */
+ mutex_lock(&ctx->state_mutex);
break;
+ }
spu = ctx->spu;
if (unlikely(test_and_clear_bit(SPU_SCHED_NOTIFY_ACTIVE,
&ctx->sched_flags))) {
@@ -388,16 +395,14 @@ long spufs_run_spu(struct spu_context *ctx, u32 *npc, u32 *event)
SPU_STATUS_STOPPED_BY_HALT |
SPU_STATUS_SINGLE_STEP)));
- if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
- (((status >> SPU_STOP_STATUS_SHIFT) & 0x3f00) == 0x2100) &&
- (ctx->state == SPU_STATE_RUNNABLE))
- ctx->stats.libassist++;
-
-
spu_disable_spu(ctx);
ret = spu_run_fini(ctx, npc, &status);
spu_yield(ctx);
+ if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
+ (((status >> SPU_STOP_STATUS_SHIFT) & 0x3f00) == 0x2100))
+ ctx->stats.libassist++;
+
if ((ret == 0) ||
((ret == -ERESTARTSYS) &&
((status & SPU_STATUS_STOPPED_BY_HALT) ||
diff --git a/arch/powerpc/platforms/cell/spufs/spufs.h b/arch/powerpc/platforms/cell/spufs/spufs.h
index 795a1b52538..2c2fe3c07d7 100644
--- a/arch/powerpc/platforms/cell/spufs/spufs.h
+++ b/arch/powerpc/platforms/cell/spufs/spufs.h
@@ -268,6 +268,9 @@ extern char *isolated_loader;
* Same as wait_event_interruptible(), except that here
* we need to call spu_release(ctx) before sleeping, and
* then spu_acquire(ctx) when awoken.
+ *
+ * Returns with state_mutex re-acquired when successfull or
+ * with -ERESTARTSYS and the state_mutex dropped when interrupted.
*/
#define spufs_wait(wq, condition) \
@@ -278,11 +281,11 @@ extern char *isolated_loader;
prepare_to_wait(&(wq), &__wait, TASK_INTERRUPTIBLE); \
if (condition) \
break; \
+ spu_release(ctx); \
if (signal_pending(current)) { \
__ret = -ERESTARTSYS; \
break; \
} \
- spu_release(ctx); \
schedule(); \
__ret = spu_acquire(ctx); \
if (__ret) \
diff --git a/arch/powerpc/platforms/powermac/feature.c b/arch/powerpc/platforms/powermac/feature.c
index ba931be2175..5169ecc3712 100644
--- a/arch/powerpc/platforms/powermac/feature.c
+++ b/arch/powerpc/platforms/powermac/feature.c
@@ -2565,6 +2565,8 @@ static void __init probe_uninorth(void)
/* Locate core99 Uni-N */
uninorth_node = of_find_node_by_name(NULL, "uni-n");
+ uninorth_maj = 1;
+
/* Locate G5 u3 */
if (uninorth_node == NULL) {
uninorth_node = of_find_node_by_name(NULL, "u3");
@@ -2575,8 +2577,10 @@ static void __init probe_uninorth(void)
uninorth_node = of_find_node_by_name(NULL, "u4");
uninorth_maj = 4;
}
- if (uninorth_node == NULL)
+ if (uninorth_node == NULL) {
+ uninorth_maj = 0;
return;
+ }
addrp = of_get_property(uninorth_node, "reg", NULL);
if (addrp == NULL)
@@ -3029,3 +3033,8 @@ void pmac_resume_agp_for_card(struct pci_dev *dev)
pmac_agp_resume(pmac_agp_bridge);
}
EXPORT_SYMBOL(pmac_resume_agp_for_card);
+
+int pmac_get_uninorth_variant(void)
+{
+ return uninorth_maj;
+}
diff --git a/drivers/macintosh/smu.c b/drivers/macintosh/smu.c
index 8ba49385c3f..77ad192962c 100644
--- a/drivers/macintosh/smu.c
+++ b/drivers/macintosh/smu.c
@@ -85,6 +85,7 @@ struct smu_device {
u32 cmd_buf_abs; /* command buffer absolute */
struct list_head cmd_list;
struct smu_cmd *cmd_cur; /* pending command */
+ int broken_nap;
struct list_head cmd_i2c_list;
struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */
struct timer_list i2c_timer;
@@ -135,6 +136,19 @@ static void smu_start_cmd(void)
fend = faddr + smu->cmd_buf->length + 2;
flush_inval_dcache_range(faddr, fend);
+
+ /* We also disable NAP mode for the duration of the command
+ * on U3 based machines.
+ * This is slightly racy as it can be written back to 1 by a sysctl
+ * but that never happens in practice. There seem to be an issue with
+ * U3 based machines such as the iMac G5 where napping for the
+ * whole duration of the command prevents the SMU from fetching it
+ * from memory. This might be related to the strange i2c based
+ * mechanism the SMU uses to access memory.
+ */
+ if (smu->broken_nap)
+ powersave_nap = 0;
+
/* This isn't exactly a DMA mapping here, I suspect
* the SMU is actually communicating with us via i2c to the
* northbridge or the CPU to access RAM.
@@ -211,6 +225,10 @@ static irqreturn_t smu_db_intr(int irq, void *arg)
misc = cmd->misc;
mb();
cmd->status = rc;
+
+ /* Re-enable NAP mode */
+ if (smu->broken_nap)
+ powersave_nap = 1;
bail:
/* Start next command if any */
smu_start_cmd();
@@ -461,7 +479,7 @@ int __init smu_init (void)
if (np == NULL)
return -ENODEV;
- printk(KERN_INFO "SMU driver %s %s\n", VERSION, AUTHOR);
+ printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
if (smu_cmdbuf_abs == 0) {
printk(KERN_ERR "SMU: Command buffer not allocated !\n");
@@ -533,6 +551,11 @@ int __init smu_init (void)
goto fail;
}
+ /* U3 has an issue with NAP mode when issuing SMU commands */
+ smu->broken_nap = pmac_get_uninorth_variant() < 4;
+ if (smu->broken_nap)
+ printk(KERN_INFO "SMU: using NAP mode workaround\n");
+
sys_ctrler = SYS_CTRLER_SMU;
return 0;
diff --git a/include/asm-powerpc/pmac_feature.h b/include/asm-powerpc/pmac_feature.h
index 26bcb0aa164..877c35a4356 100644
--- a/include/asm-powerpc/pmac_feature.h
+++ b/include/asm-powerpc/pmac_feature.h
@@ -392,6 +392,14 @@ extern u32 __iomem *uninorth_base;
#define UN_BIS(r,v) (UN_OUT((r), UN_IN(r) | (v)))
#define UN_BIC(r,v) (UN_OUT((r), UN_IN(r) & ~(v)))
+/* Uninorth variant:
+ *
+ * 0 = not uninorth
+ * 1 = U1.x or U2.x
+ * 3 = U3
+ * 4 = U4
+ */
+extern int pmac_get_uninorth_variant(void);
#endif /* __ASM_POWERPC_PMAC_FEATURE_H */
#endif /* __KERNEL__ */
diff --git a/kernel/resource.c b/kernel/resource.c
index 2eb553d9b51..82aea814d40 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -228,7 +228,7 @@ int release_resource(struct resource *old)
EXPORT_SYMBOL(release_resource);
-#ifdef CONFIG_MEMORY_HOTPLUG
+#if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
/*
* Finds the lowest memory reosurce exists within [res->start.res->end)
* the caller must specify res->start, res->end, res->flags.