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);