3 files changed, 42 insertions, 7 deletions

diff --git a/arch/arm/include/asm/hardware/pl080.h b/arch/arm/include/asm/hardware/pl080.h
index 33c78d7af2e1..4eea2107214b 100644
--- a/arch/arm/include/asm/hardware/pl080.h
+++ b/arch/arm/include/asm/hardware/pl080.h
@@ -102,6 +102,8 @@
 #define PL080_WIDTH_16BIT                       (0x1)
 #define PL080_WIDTH_32BIT                       (0x2)
 
+#define PL080N_CONFIG_ITPROT                    (1 << 20)
+#define PL080N_CONFIG_SECPROT                   (1 << 19)
 #define PL080_CONFIG_HALT                       (1 << 18)
 #define PL080_CONFIG_ACTIVE                     (1 << 17)  /* RO */
 #define PL080_CONFIG_LOCK                       (1 << 16)
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index 08589c683e2b..629250e36d3b 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -95,10 +95,14 @@ static struct amba_driver pl08x_amba_driver;
  * struct vendor_data - vendor-specific config parameters for PL08x derivatives
  * @channels: the number of channels available in this variant
  * @dualmaster: whether this version supports dual AHB masters or not.
+ * @nomadik: whether the channels have Nomadik security extension bits
+ *      that need to be checked for permission before use and some registers are
+ *      missing
  */
 struct vendor_data {
         u8 channels;
         bool dualmaster;
+        bool nomadik;
 };
 
 /*
@@ -385,7 +389,7 @@ pl08x_get_phy_channel(struct pl08x_driver_data *pl08x,
 
                 spin_lock_irqsave(&ch->lock, flags);
 
-                if (!ch->serving) {
+                if (!ch->locked && !ch->serving) {
                         ch->serving = virt_chan;
                         ch->signal = -1;
                         spin_unlock_irqrestore(&ch->lock, flags);
@@ -1483,6 +1487,9 @@ bool pl08x_filter_id(struct dma_chan *chan, void *chan_id)
  */
 static void pl08x_ensure_on(struct pl08x_driver_data *pl08x)
 {
+        /* The Nomadik variant does not have the config register */
+        if (pl08x->vd->nomadik)
+                return;
         writel(PL080_CONFIG_ENABLE, pl08x->base + PL080_CONFIG);
 }
 
@@ -1772,8 +1779,10 @@ static int pl08x_debugfs_show(struct seq_file *s, void *data)
                 spin_lock_irqsave(&ch->lock, flags);
                 virt_chan = ch->serving;
 
-                seq_printf(s, "%d\t\t%s\n",
-                           ch->id, virt_chan ? virt_chan->name : "(none)");
+                seq_printf(s, "%d\t\t%s%s\n",
+                           ch->id,
+                           virt_chan ? virt_chan->name : "(none)",
+                           ch->locked ? " LOCKED" : "");
 
                 spin_unlock_irqrestore(&ch->lock, flags);
         }
@@ -1917,7 +1926,7 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
         }
 
         /* Initialize physical channels */
-        pl08x->phy_chans = kmalloc((vd->channels * sizeof(*pl08x->phy_chans)),
+        pl08x->phy_chans = kzalloc((vd->channels * sizeof(*pl08x->phy_chans)),
                         GFP_KERNEL);
         if (!pl08x->phy_chans) {
                 dev_err(&adev->dev, "%s failed to allocate "
@@ -1932,8 +1941,23 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
                 ch->id = i;
                 ch->base = pl08x->base + PL080_Cx_BASE(i);
                 spin_lock_init(&ch->lock);
-                ch->serving = NULL;
                 ch->signal = -1;
+
+                /*
+                 * Nomadik variants can have channels that are locked
+                 * down for the secure world only. Lock up these channels
+                 * by perpetually serving a dummy virtual channel.
+                 */
+                if (vd->nomadik) {
+                        u32 val;
+
+                        val = readl(ch->base + PL080_CH_CONFIG);
+                        if (val & (PL080N_CONFIG_ITPROT | PL080N_CONFIG_SECPROT)) {
+                                dev_info(&adev->dev, "physical channel %d reserved for secure access only\n", i);
+                                ch->locked = true;
+                        }
+                }
+
                 dev_dbg(&adev->dev, "physical channel %d is %s\n",
                         i, pl08x_phy_channel_busy(ch) ? "BUSY" : "FREE");
         }
@@ -2016,6 +2040,12 @@ static struct vendor_data vendor_pl080 = {
         .dualmaster = true,
 };
 
+static struct vendor_data vendor_nomadik = {
+        .channels = 8,
+        .dualmaster = true,
+        .nomadik = true,
+};
+
 static struct vendor_data vendor_pl081 = {
         .channels = 2,
         .dualmaster = false,
@@ -2036,9 +2066,9 @@ static struct amba_id pl08x_ids[] = {
         },
         /* Nomadik 8815 PL080 variant */
         {
-                .id     = 0x00280880,
+                .id     = 0x00280080,
                 .mask   = 0x00ffffff,
-                .data   = &vendor_pl080,
+                .data   = &vendor_nomadik,
         },
         { 0, 0 },
 };
diff --git a/include/linux/amba/pl08x.h b/include/linux/amba/pl08x.h
index e64ce2cfee99..02549017212a 100644
--- a/include/linux/amba/pl08x.h
+++ b/include/linux/amba/pl08x.h
@@ -92,6 +92,8 @@ struct pl08x_bus_data {
  * right now
  * @serving: the virtual channel currently being served by this physical
  * channel
+ * @locked: channel unavailable for the system, e.g. dedicated to secure
+ * world
  */
 struct pl08x_phy_chan {
         unsigned int id;
@@ -99,6 +101,7 @@ struct pl08x_phy_chan {
         spinlock_t lock;
         int signal;
         struct pl08x_dma_chan *serving;
+        bool locked;
 };
 
 /**