Merge tag 'powerpc-3.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc updates from Michael Ellerman:
 "Some nice cleanups like removing bootmem, and removal of
  __get_cpu_var().

  There is one patch to mm/gup.c.  This is the generic GUP
  implementation, but is only used by us and arm(64).  We have an ack
  from Steve Capper, and although we didn't get an ack from Andrew he
  told us to take the patch through the powerpc tree.

  There's one cxl patch.  This is in drivers/misc, but Greg said he was
  happy for us to manage fixes for it.

  There is an infrastructure patch to support an IPMI driver for OPAL.

  There is also an RTC driver for OPAL.  We weren't able to get any
  response from the RTC maintainer, Alessandro Zummo, so in the end we
  just merged the driver.

  The usual batch of Freescale updates from Scott"

* tag 'powerpc-3.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (101 commits)
  powerpc/powernv: Return to cpu offline loop when finished in KVM guest
  powerpc/book3s: Fix partial invalidation of TLBs in MCE code.
  powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault
  powerpc/xmon: Cleanup the breakpoint flags
  powerpc/xmon: Enable HW instruction breakpoint on POWER8
  powerpc/mm/thp: Use tlbiel if possible
  powerpc/mm/thp: Remove code duplication
  powerpc/mm/hugetlb: Sanity check gigantic hugepage count
  powerpc/oprofile: Disable pagefaults during user stack read
  powerpc/mm: Check for matching hpte without taking hpte lock
  powerpc: Drop useless warning in eeh_init()
  powerpc/powernv: Cleanup unused MCE definitions/declarations.
  powerpc/eeh: Dump PHB diag-data early
  powerpc/eeh: Recover EEH error on ownership change for BCM5719
  powerpc/eeh: Set EEH_PE_RESET on PE reset
  powerpc/eeh: Refactor eeh_reset_pe()
  powerpc: Remove more traces of bootmem
  powerpc/pseries: Initialise nvram_pstore_info's buf_lock
  cxl: Name interrupts in /proc/interrupt
  cxl: Return error to PSL if IRQ demultiplexing fails & print clearer warning
  ...

7 files changed, 414 insertions, 40 deletions

diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h
index 3d2b8677ec8a..b5b6bda44a00 100644
--- a/drivers/misc/cxl/cxl.h
+++ b/drivers/misc/cxl/cxl.h
@@ -336,6 +336,8 @@ struct cxl_sste {
 struct cxl_afu {
 	irq_hw_number_t psl_hwirq;
 	irq_hw_number_t serr_hwirq;
+	char *err_irq_name;
+	char *psl_irq_name;
 	unsigned int serr_virq;
 	void __iomem *p1n_mmio;
 	void __iomem *p2n_mmio;
@@ -379,6 +381,12 @@ struct cxl_afu {
 	bool enabled;
 };
 
+
+struct cxl_irq_name {
+	struct list_head list;
+	char *name;
+};
+
 /*
  * This is a cxl context.  If the PSL is in dedicated mode, there will be one
  * of these per AFU.  If in AFU directed there can be lots of these.
@@ -403,6 +411,7 @@ struct cxl_context {
 
 	unsigned long *irq_bitmap; /* Accessed from IRQ context */
 	struct cxl_irq_ranges irqs;
+	struct list_head irq_names;
 	u64 fault_addr;
 	u64 fault_dsisr;
 	u64 afu_err;
@@ -444,6 +453,7 @@ struct cxl {
 	struct dentry *trace;
 	struct dentry *psl_err_chk;
 	struct dentry *debugfs;
+	char *irq_name;
 	struct bin_attribute cxl_attr;
 	int adapter_num;
 	int user_irqs;
@@ -563,9 +573,6 @@ int _cxl_afu_deactivate_mode(struct cxl_afu *afu, int mode);
 int cxl_afu_deactivate_mode(struct cxl_afu *afu);
 int cxl_afu_select_best_mode(struct cxl_afu *afu);
 
-unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
-		         irq_handler_t handler, void *cookie);
-void cxl_unmap_irq(unsigned int virq, void *cookie);
 int cxl_register_psl_irq(struct cxl_afu *afu);
 void cxl_release_psl_irq(struct cxl_afu *afu);
 int cxl_register_psl_err_irq(struct cxl *adapter);
@@ -612,7 +619,7 @@ int cxl_attach_process(struct cxl_context *ctx, bool kernel, u64 wed,
 			    u64 amr);
 int cxl_detach_process(struct cxl_context *ctx);
 
-int cxl_get_irq(struct cxl_context *ctx, struct cxl_irq_info *info);
+int cxl_get_irq(struct cxl_afu *afu, struct cxl_irq_info *info);
 int cxl_ack_irq(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask);
 
 int cxl_check_error(struct cxl_afu *afu);
diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
index c99e896604ee..f8684bca2d79 100644
--- a/drivers/misc/cxl/fault.c
+++ b/drivers/misc/cxl/fault.c
@@ -133,7 +133,7 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
 {
 	unsigned flt = 0;
 	int result;
-	unsigned long access, flags;
+	unsigned long access, flags, inv_flags = 0;
 
 	if ((result = copro_handle_mm_fault(mm, dar, dsisr, &flt))) {
 		pr_devel("copro_handle_mm_fault failed: %#x\n", result);
@@ -149,8 +149,12 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
 		access |= _PAGE_RW;
 	if ((!ctx->kernel) || ~(dar & (1ULL << 63)))
 		access |= _PAGE_USER;
+
+	if (dsisr & DSISR_NOHPTE)
+		inv_flags |= HPTE_NOHPTE_UPDATE;
+
 	local_irq_save(flags);
-	hash_page_mm(mm, dar, access, 0x300);
+	hash_page_mm(mm, dar, access, 0x300, inv_flags);
 	local_irq_restore(flags);
 
 	pr_devel("Page fault successfully handled for pe: %i!\n", ctx->pe);
diff --git a/drivers/misc/cxl/irq.c b/drivers/misc/cxl/irq.c
index 336020c8e1af..c294925f73ee 100644
--- a/drivers/misc/cxl/irq.c
+++ b/drivers/misc/cxl/irq.c
@@ -92,20 +92,13 @@ static irqreturn_t schedule_cxl_fault(struct cxl_context *ctx, u64 dsisr, u64 da
 	return IRQ_HANDLED;
 }
 
-static irqreturn_t cxl_irq(int irq, void *data)
+static irqreturn_t cxl_irq(int irq, void *data, struct cxl_irq_info *irq_info)
 {
 	struct cxl_context *ctx = data;
-	struct cxl_irq_info irq_info;
 	u64 dsisr, dar;
-	int result;
-
-	if ((result = cxl_get_irq(ctx, &irq_info))) {
-		WARN(1, "Unable to get CXL IRQ Info: %i\n", result);
-		return IRQ_HANDLED;
-	}
 
-	dsisr = irq_info.dsisr;
-	dar = irq_info.dar;
+	dsisr = irq_info->dsisr;
+	dar = irq_info->dar;
 
 	pr_devel("CXL interrupt %i for afu pe: %i DSISR: %#llx DAR: %#llx\n", irq, ctx->pe, dsisr, dar);
 
@@ -149,9 +142,9 @@ static irqreturn_t cxl_irq(int irq, void *data)
 	if (dsisr & CXL_PSL_DSISR_An_UR)
 		pr_devel("CXL interrupt: AURP PTE not found\n");
 	if (dsisr & CXL_PSL_DSISR_An_PE)
-		return handle_psl_slice_error(ctx, dsisr, irq_info.errstat);
+		return handle_psl_slice_error(ctx, dsisr, irq_info->errstat);
 	if (dsisr & CXL_PSL_DSISR_An_AE) {
-		pr_devel("CXL interrupt: AFU Error %.llx\n", irq_info.afu_err);
+		pr_devel("CXL interrupt: AFU Error %.llx\n", irq_info->afu_err);
 
 		if (ctx->pending_afu_err) {
 			/*
@@ -163,10 +156,10 @@ static irqreturn_t cxl_irq(int irq, void *data)
 			 */
 			dev_err_ratelimited(&ctx->afu->dev, "CXL AFU Error "
 					    "undelivered to pe %i: %.llx\n",
-					    ctx->pe, irq_info.afu_err);
+					    ctx->pe, irq_info->afu_err);
 		} else {
 			spin_lock(&ctx->lock);
-			ctx->afu_err = irq_info.afu_err;
+			ctx->afu_err = irq_info->afu_err;
 			ctx->pending_afu_err = 1;
 			spin_unlock(&ctx->lock);
 
@@ -182,24 +175,43 @@ static irqreturn_t cxl_irq(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t fail_psl_irq(struct cxl_afu *afu, struct cxl_irq_info *irq_info)
+{
+	if (irq_info->dsisr & CXL_PSL_DSISR_TRANS)
+		cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_AE);
+	else
+		cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_A);
+
+	return IRQ_HANDLED;
+}
+
 static irqreturn_t cxl_irq_multiplexed(int irq, void *data)
 {
 	struct cxl_afu *afu = data;
 	struct cxl_context *ctx;
+	struct cxl_irq_info irq_info;
 	int ph = cxl_p2n_read(afu, CXL_PSL_PEHandle_An) & 0xffff;
 	int ret;
 
+	if ((ret = cxl_get_irq(afu, &irq_info))) {
+		WARN(1, "Unable to get CXL IRQ Info: %i\n", ret);
+		return fail_psl_irq(afu, &irq_info);
+	}
+
 	rcu_read_lock();
 	ctx = idr_find(&afu->contexts_idr, ph);
 	if (ctx) {
-		ret = cxl_irq(irq, ctx);
+		ret = cxl_irq(irq, ctx, &irq_info);
 		rcu_read_unlock();
 		return ret;
 	}
 	rcu_read_unlock();
 
-	WARN(1, "Unable to demultiplex CXL PSL IRQ\n");
-	return IRQ_HANDLED;
+	WARN(1, "Unable to demultiplex CXL PSL IRQ for PE %i DSISR %.16llx DAR"
+		" %.16llx\n(Possible AFU HW issue - was a term/remove acked"
+		" with outstanding transactions?)\n", ph, irq_info.dsisr,
+		irq_info.dar);
+	return fail_psl_irq(afu, &irq_info);
 }
 
 static irqreturn_t cxl_irq_afu(int irq, void *data)
@@ -243,7 +255,7 @@ static irqreturn_t cxl_irq_afu(int irq, void *data)
 }
 
 unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
-			 irq_handler_t handler, void *cookie)
+			 irq_handler_t handler, void *cookie, const char *name)
 {
 	unsigned int virq;
 	int result;
@@ -259,7 +271,7 @@ unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
 
 	pr_devel("hwirq %#lx mapped to virq %u\n", hwirq, virq);
 
-	result = request_irq(virq, handler, 0, "cxl", cookie);
+	result = request_irq(virq, handler, 0, name, cookie);
 	if (result) {
 		dev_warn(&adapter->dev, "cxl_map_irq: request_irq failed: %i\n", result);
 		return 0;
@@ -278,14 +290,15 @@ static int cxl_register_one_irq(struct cxl *adapter,
 				irq_handler_t handler,
 				void *cookie,
 				irq_hw_number_t *dest_hwirq,
-				unsigned int *dest_virq)
+				unsigned int *dest_virq,
+				const char *name)
 {
 	int hwirq, virq;
 
 	if ((hwirq = cxl_alloc_one_irq(adapter)) < 0)
 		return hwirq;
 
-	if (!(virq = cxl_map_irq(adapter, hwirq, handler, cookie)))
+	if (!(virq = cxl_map_irq(adapter, hwirq, handler, cookie, name)))
 		goto err;
 
 	*dest_hwirq = hwirq;
@@ -302,10 +315,19 @@ int cxl_register_psl_err_irq(struct cxl *adapter)
 {
 	int rc;
 
+	adapter->irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
+				      dev_name(&adapter->dev));
+	if (!adapter->irq_name)
+		return -ENOMEM;
+
 	if ((rc = cxl_register_one_irq(adapter, cxl_irq_err, adapter,
 				       &adapter->err_hwirq,
-				       &adapter->err_virq)))
+				       &adapter->err_virq,
+				       adapter->irq_name))) {
+		kfree(adapter->irq_name);
+		adapter->irq_name = NULL;
 		return rc;
+	}
 
 	cxl_p1_write(adapter, CXL_PSL_ErrIVTE, adapter->err_hwirq & 0xffff);
 
@@ -317,6 +339,7 @@ void cxl_release_psl_err_irq(struct cxl *adapter)
 	cxl_p1_write(adapter, CXL_PSL_ErrIVTE, 0x0000000000000000);
 	cxl_unmap_irq(adapter->err_virq, adapter);
 	cxl_release_one_irq(adapter, adapter->err_hwirq);
+	kfree(adapter->irq_name);
 }
 
 int cxl_register_serr_irq(struct cxl_afu *afu)
@@ -324,10 +347,18 @@ int cxl_register_serr_irq(struct cxl_afu *afu)
 	u64 serr;
 	int rc;
 
+	afu->err_irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
+				      dev_name(&afu->dev));
+	if (!afu->err_irq_name)
+		return -ENOMEM;
+
 	if ((rc = cxl_register_one_irq(afu->adapter, cxl_slice_irq_err, afu,
 				       &afu->serr_hwirq,
-				       &afu->serr_virq)))
+				       &afu->serr_virq, afu->err_irq_name))) {
+		kfree(afu->err_irq_name);
+		afu->err_irq_name = NULL;
 		return rc;
+	}
 
 	serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
 	serr = (serr & 0x00ffffffffff0000ULL) | (afu->serr_hwirq & 0xffff);
@@ -341,24 +372,50 @@ void cxl_release_serr_irq(struct cxl_afu *afu)
 	cxl_p1n_write(afu, CXL_PSL_SERR_An, 0x0000000000000000);
 	cxl_unmap_irq(afu->serr_virq, afu);
 	cxl_release_one_irq(afu->adapter, afu->serr_hwirq);
+	kfree(afu->err_irq_name);
 }
 
 int cxl_register_psl_irq(struct cxl_afu *afu)
 {
-	return cxl_register_one_irq(afu->adapter, cxl_irq_multiplexed, afu,
-			&afu->psl_hwirq, &afu->psl_virq);
+	int rc;
+
+	afu->psl_irq_name = kasprintf(GFP_KERNEL, "cxl-%s",
+				      dev_name(&afu->dev));
+	if (!afu->psl_irq_name)
+		return -ENOMEM;
+
+	if ((rc = cxl_register_one_irq(afu->adapter, cxl_irq_multiplexed, afu,
+				    &afu->psl_hwirq, &afu->psl_virq,
+				    afu->psl_irq_name))) {
+		kfree(afu->psl_irq_name);
+		afu->psl_irq_name = NULL;
+	}
+	return rc;
 }
 
 void cxl_release_psl_irq(struct cxl_afu *afu)
 {
 	cxl_unmap_irq(afu->psl_virq, afu);
 	cxl_release_one_irq(afu->adapter, afu->psl_hwirq);
+	kfree(afu->psl_irq_name);
+}
+
+void afu_irq_name_free(struct cxl_context *ctx)
+{
+	struct cxl_irq_name *irq_name, *tmp;
+
+	list_for_each_entry_safe(irq_name, tmp, &ctx->irq_names, list) {
+		kfree(irq_name->name);
+		list_del(&irq_name->list);
+		kfree(irq_name);
+	}
 }
 
 int afu_register_irqs(struct cxl_context *ctx, u32 count)
 {
 	irq_hw_number_t hwirq;
-	int rc, r, i;
+	int rc, r, i, j = 1;
+	struct cxl_irq_name *irq_name;
 
 	if ((rc = cxl_alloc_irq_ranges(&ctx->irqs, ctx->afu->adapter, count)))
 		return rc;
@@ -372,15 +429,47 @@ int afu_register_irqs(struct cxl_context *ctx, u32 count)
 				  sizeof(*ctx->irq_bitmap), GFP_KERNEL);
 	if (!ctx->irq_bitmap)
 		return -ENOMEM;
+
+	/*
+	 * Allocate names first.  If any fail, bail out before allocating
+	 * actual hardware IRQs.
+	 */
+	INIT_LIST_HEAD(&ctx->irq_names);
+	for (r = 1; r < CXL_IRQ_RANGES; r++) {
+		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
+			irq_name = kmalloc(sizeof(struct cxl_irq_name),
+					   GFP_KERNEL);
+			if (!irq_name)
+				goto out;
+			irq_name->name = kasprintf(GFP_KERNEL, "cxl-%s-pe%i-%i",
+						   dev_name(&ctx->afu->dev),
+						   ctx->pe, j);
+			if (!irq_name->name) {
+				kfree(irq_name);
+				goto out;
+			}
+			/* Add to tail so next look get the correct order */
+			list_add_tail(&irq_name->list, &ctx->irq_names);
+			j++;
+		}
+	}
+
+	/* We've allocated all memory now, so let's do the irq allocations */
+	irq_name = list_first_entry(&ctx->irq_names, struct cxl_irq_name, list);
 	for (r = 1; r < CXL_IRQ_RANGES; r++) {
 		hwirq = ctx->irqs.offset[r];
 		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
 			cxl_map_irq(ctx->afu->adapter, hwirq,
-				     cxl_irq_afu, ctx);
+				    cxl_irq_afu, ctx, irq_name->name);
+			irq_name = list_next_entry(irq_name, list);
 		}
 	}
 
 	return 0;
+
+out:
+	afu_irq_name_free(ctx);
+	return -ENOMEM;
 }
 
 void afu_release_irqs(struct cxl_context *ctx)
@@ -398,5 +487,6 @@ void afu_release_irqs(struct cxl_context *ctx)
 		}
 	}
 
+	afu_irq_name_free(ctx);
 	cxl_release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
 }
diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c
index d47532e8f4f1..9a5a442269a8 100644
--- a/drivers/misc/cxl/native.c
+++ b/drivers/misc/cxl/native.c
@@ -637,18 +637,18 @@ int cxl_detach_process(struct cxl_context *ctx)
 	return detach_process_native_afu_directed(ctx);
 }
 
-int cxl_get_irq(struct cxl_context *ctx, struct cxl_irq_info *info)
+int cxl_get_irq(struct cxl_afu *afu, struct cxl_irq_info *info)
 {
 	u64 pidtid;
 
-	info->dsisr = cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An);
-	info->dar = cxl_p2n_read(ctx->afu, CXL_PSL_DAR_An);
-	info->dsr = cxl_p2n_read(ctx->afu, CXL_PSL_DSR_An);
-	pidtid = cxl_p2n_read(ctx->afu, CXL_PSL_PID_TID_An);
+	info->dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
+	info->dar = cxl_p2n_read(afu, CXL_PSL_DAR_An);
+	info->dsr = cxl_p2n_read(afu, CXL_PSL_DSR_An);
+	pidtid = cxl_p2n_read(afu, CXL_PSL_PID_TID_An);
 	info->pid = pidtid >> 32;
 	info->tid = pidtid & 0xffffffff;
-	info->afu_err = cxl_p2n_read(ctx->afu, CXL_AFU_ERR_An);
-	info->errstat = cxl_p2n_read(ctx->afu, CXL_PSL_ErrStat_An);
+	info->afu_err = cxl_p2n_read(afu, CXL_AFU_ERR_An);
+	info->errstat = cxl_p2n_read(afu, CXL_PSL_ErrStat_An);
 
 	return 0;
 }
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 4511ddc1ac31..f15cddfeb897 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -987,6 +987,17 @@ config RTC_DRV_NUC900
 	  If you say yes here you get support for the RTC subsystem of the
 	  NUC910/NUC920 used in embedded systems.
 
+config RTC_DRV_OPAL
+	tristate "IBM OPAL RTC driver"
+	depends on PPC_POWERNV
+	default y
+	help
+	  If you say yes here you get support for the PowerNV platform RTC
+	  driver based on OPAL interfaces.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called rtc-opal.
+
 comment "on-CPU RTC drivers"
 
 config RTC_DRV_DAVINCI
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index b188323c096a..c8ef3e1e6ccd 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -92,6 +92,7 @@ obj-$(CONFIG_RTC_DRV_MSM6242)	+= rtc-msm6242.o
 obj-$(CONFIG_RTC_DRV_MPC5121)	+= rtc-mpc5121.o
 obj-$(CONFIG_RTC_DRV_MV)	+= rtc-mv.o
 obj-$(CONFIG_RTC_DRV_NUC900)	+= rtc-nuc900.o
+obj-$(CONFIG_RTC_DRV_OPAL)	+= rtc-opal.o
 obj-$(CONFIG_RTC_DRV_OMAP)	+= rtc-omap.o
 obj-$(CONFIG_RTC_DRV_PALMAS)	+= rtc-palmas.o
 obj-$(CONFIG_RTC_DRV_PCAP)	+= rtc-pcap.o
diff --git a/drivers/rtc/rtc-opal.c b/drivers/rtc/rtc-opal.c
new file mode 100644
index 000000000000..95f652165fe9
--- /dev/null
+++ b/drivers/rtc/rtc-opal.c
@@ -0,0 +1,261 @@
+/*
+ * IBM OPAL RTC driver
+ * Copyright (C) 2014 IBM
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.
+ */
+
+#define DRVNAME		"rtc-opal"
+#define pr_fmt(fmt)	DRVNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/bcd.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <asm/opal.h>
+#include <asm/firmware.h>
+
+static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm)
+{
+	tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) +
+		       bcd2bin((y_m_d >> 16) & 0xff)) - 1900;
+	tm->tm_mon  = bcd2bin((y_m_d >> 8) & 0xff) - 1;
+	tm->tm_mday = bcd2bin(y_m_d & 0xff);
+	tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff);
+	tm->tm_min  = bcd2bin((h_m_s_ms >> 48) & 0xff);
+	tm->tm_sec  = bcd2bin((h_m_s_ms >> 40) & 0xff);
+
+	GregorianDay(tm);
+}
+
+static void tm_to_opal(struct rtc_time *tm, u32 *y_m_d, u64 *h_m_s_ms)
+{
+	*y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24;
+	*y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16;
+	*y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8;
+	*y_m_d |= ((u32)bin2bcd(tm->tm_mday));
+
+	*h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56;
+	*h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48;
+	*h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40;
+}
+
+static int opal_get_rtc_time(struct device *dev, struct rtc_time *tm)
+{
+	long rc = OPAL_BUSY;
+	u32 y_m_d;
+	u64 h_m_s_ms;
+	__be32 __y_m_d;
+	__be64 __h_m_s_ms;
+
+	while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+		rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms);
+		if (rc == OPAL_BUSY_EVENT)
+			opal_poll_events(NULL);
+		else
+			msleep(10);
+	}
+
+	if (rc != OPAL_SUCCESS)
+		return -EIO;
+
+	y_m_d = be32_to_cpu(__y_m_d);
+	h_m_s_ms = be64_to_cpu(__h_m_s_ms);
+	opal_to_tm(y_m_d, h_m_s_ms, tm);
+
+	return 0;
+}
+
+static int opal_set_rtc_time(struct device *dev, struct rtc_time *tm)
+{
+	long rc = OPAL_BUSY;
+	u32 y_m_d = 0;
+	u64 h_m_s_ms = 0;
+
+	tm_to_opal(tm, &y_m_d, &h_m_s_ms);
+	while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+		rc = opal_rtc_write(y_m_d, h_m_s_ms);
+		if (rc == OPAL_BUSY_EVENT)
+			opal_poll_events(NULL);
+		else
+			msleep(10);
+	}
+
+	return rc == OPAL_SUCCESS ? 0 : -EIO;
+}
+
+/*
+ * TPO	Timed Power-On
+ *
+ * TPO get/set OPAL calls care about the hour and min and to make it consistent
+ * with the rtc utility time conversion functions, we use the 'u64' to store
+ * its value and perform bit shift by 32 before use..
+ */
+static int opal_get_tpo_time(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	__be32 __y_m_d, __h_m;
+	struct opal_msg msg;
+	int rc, token;
+	u64 h_m_s_ms;
+	u32 y_m_d;
+
+	token = opal_async_get_token_interruptible();
+	if (token < 0) {
+		if (token != -ERESTARTSYS)
+			pr_err("Failed to get the async token\n");
+
+		return token;
+	}
+
+	rc = opal_tpo_read(token, &__y_m_d, &__h_m);
+	if (rc != OPAL_ASYNC_COMPLETION) {
+		rc = -EIO;
+		goto exit;
+	}
+
+	rc = opal_async_wait_response(token, &msg);
+	if (rc) {
+		rc = -EIO;
+		goto exit;
+	}
+
+	rc = be64_to_cpu(msg.params[1]);
+	if (rc != OPAL_SUCCESS) {
+		rc = -EIO;
+		goto exit;
+	}
+
+	y_m_d = be32_to_cpu(__y_m_d);
+	h_m_s_ms = ((u64)be32_to_cpu(__h_m) << 32);
+	opal_to_tm(y_m_d, h_m_s_ms, &alarm->time);
+
+exit:
+	opal_async_release_token(token);
+	return rc;
+}
+
+/* Set Timed Power-On */
+static int opal_set_tpo_time(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	u64 h_m_s_ms = 0, token;
+	struct opal_msg msg;
+	u32 y_m_d = 0;
+	int rc;
+
+	tm_to_opal(&alarm->time, &y_m_d, &h_m_s_ms);
+
+	token = opal_async_get_token_interruptible();
+	if (token < 0) {
+		if (token != -ERESTARTSYS)
+			pr_err("Failed to get the async token\n");
+
+		return token;
+	}
+
+	/* TPO, we care about hour and minute */
+	rc = opal_tpo_write(token, y_m_d,
+			    (u32)((h_m_s_ms >> 32) & 0xffff0000));
+	if (rc != OPAL_ASYNC_COMPLETION) {
+		rc = -EIO;
+		goto exit;
+	}
+
+	rc = opal_async_wait_response(token, &msg);
+	if (rc) {
+		rc = -EIO;
+		goto exit;
+	}
+
+	rc = be64_to_cpu(msg.params[1]);
+	if (rc != OPAL_SUCCESS)
+		rc = -EIO;
+
+exit:
+	opal_async_release_token(token);
+	return rc;
+}
+
+static const struct rtc_class_ops opal_rtc_ops = {
+	.read_time	= opal_get_rtc_time,
+	.set_time	= opal_set_rtc_time,
+	.read_alarm	= opal_get_tpo_time,
+	.set_alarm	= opal_set_tpo_time,
+};
+
+static int opal_rtc_probe(struct platform_device *pdev)
+{
+	struct rtc_device *rtc;
+
+	if (pdev->dev.of_node && of_get_property(pdev->dev.of_node, "has-tpo",
+						 NULL))
+		device_set_wakeup_capable(&pdev->dev, true);
+
+	rtc = devm_rtc_device_register(&pdev->dev, DRVNAME, &opal_rtc_ops,
+				       THIS_MODULE);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	rtc->uie_unsupported = 1;
+
+	return 0;
+}
+
+static const struct of_device_id opal_rtc_match[] = {
+	{
+		.compatible	= "ibm,opal-rtc",
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, opal_rtc_match);
+
+static const struct platform_device_id opal_rtc_driver_ids[] = {
+	{
+		.name		= "opal-rtc",
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, opal_rtc_driver_ids);
+
+static struct platform_driver opal_rtc_driver = {
+	.probe		= opal_rtc_probe,
+	.id_table	= opal_rtc_driver_ids,
+	.driver		= {
+		.name		= DRVNAME,
+		.owner		= THIS_MODULE,
+		.of_match_table	= opal_rtc_match,
+	},
+};
+
+static int __init opal_rtc_init(void)
+{
+	if (!firmware_has_feature(FW_FEATURE_OPAL))
+		return -ENODEV;
+
+	return platform_driver_register(&opal_rtc_driver);
+}
+
+static void __exit opal_rtc_exit(void)
+{
+	platform_driver_unregister(&opal_rtc_driver);
+}
+
+MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("IBM OPAL RTC driver");
+MODULE_LICENSE("GPL");
+
+module_init(opal_rtc_init);
+module_exit(opal_rtc_exit);