gpu: host1x: Enable gather filter

The gather filter is a feature present on Tegra124 and newer where the
hardware prevents GATHERed command buffers from executing commands
normally reserved for the CDMA pushbuffer which is maintained by the
kernel driver.

This commit enables the gather filter on all supporting hardware.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/host1x/hw/channel_hw.c

@@ -180,10 +180,32 @@ error:
 	return err;
 }
 
+static void enable_gather_filter(struct host1x *host,
+				 struct host1x_channel *ch)
+{
+#if HOST1X_HW >= 6
+	u32 val;
+
+	if (!host->hv_regs)
+		return;
+
+	val = host1x_hypervisor_readl(
+		host, HOST1X_HV_CH_KERNEL_FILTER_GBUFFER(ch->id / 32));
+	val |= BIT(ch->id % 32);
+	host1x_hypervisor_writel(
+		host, val, HOST1X_HV_CH_KERNEL_FILTER_GBUFFER(ch->id / 32));
+#elif HOST1X_HW >= 4
+	host1x_ch_writel(ch,
+			 HOST1X_CHANNEL_CHANNELCTRL_KERNEL_FILTER_GBUFFER(1),
+			 HOST1X_CHANNEL_CHANNELCTRL);
+#endif
+}
+
 static int host1x_channel_init(struct host1x_channel *ch, struct host1x *dev,
 			       unsigned int index)
 {
 	ch->regs = dev->regs + index * HOST1X_CHANNEL_SIZE;
+	enable_gather_filter(dev, ch);
 	return 0;
 }
 

drivers/gpu/host1x/hw/hw_host1x04_channel.h

@@ -117,5 +117,17 @@ static inline u32 host1x_channel_dmactrl_dmainitget(void)
 }
 #define HOST1X_CHANNEL_DMACTRL_DMAINITGET \
 	host1x_channel_dmactrl_dmainitget()
+static inline u32 host1x_channel_channelctrl_r(void)
+{
+	return 0x98;
+}
+#define HOST1X_CHANNEL_CHANNELCTRL \
+	host1x_channel_channelctrl_r()
+static inline u32 host1x_channel_channelctrl_kernel_filter_gbuffer_f(u32 v)
+{
+	return (v & 0x1) << 2;
+}
+#define HOST1X_CHANNEL_CHANNELCTRL_KERNEL_FILTER_GBUFFER(v) \
+	host1x_channel_channelctrl_kernel_filter_gbuffer_f(v)
 
 #endif

drivers/gpu/host1x/hw/hw_host1x05_channel.h

@@ -117,5 +117,17 @@ static inline u32 host1x_channel_dmactrl_dmainitget(void)
 }
 #define HOST1X_CHANNEL_DMACTRL_DMAINITGET \
 	host1x_channel_dmactrl_dmainitget()
+static inline u32 host1x_channel_channelctrl_r(void)
+{
+	return 0x98;
+}
+#define HOST1X_CHANNEL_CHANNELCTRL \
+	host1x_channel_channelctrl_r()
+static inline u32 host1x_channel_channelctrl_kernel_filter_gbuffer_f(u32 v)
+{
+	return (v & 0x1) << 2;
+}
+#define HOST1X_CHANNEL_CHANNELCTRL_KERNEL_FILTER_GBUFFER(v) \
+	host1x_channel_channelctrl_kernel_filter_gbuffer_f(v)
 
 #endif