From: Thierry Reding <tred...@nvidia.com>
Instead of programming all SID overrides during early boot, perform the
operation on-demand after the SMMU translations have been set up for a
device. This reuses data from device tree to match memory clients for a
device and programs the SID specified in device tree, which corresponds
to the SID used for the SMMU context banks for the device.
Signed-off-by: Thierry Reding <tred...@nvidia.com>
---
drivers/memory/tegra/tegra186.c | 70 +++++++++++++++++++++++++++++++++
include/soc/tegra/mc.h | 10 +++++
2 files changed, 80 insertions(+)
diff --git a/drivers/memory/tegra/tegra186.c b/drivers/memory/tegra/tegra186.c
index efa922d51d83..a89e8e40d875 100644
--- a/drivers/memory/tegra/tegra186.c
+++ b/drivers/memory/tegra/tegra186.c
@@ -4,6 +4,7 @@
*/
#include <linux/io.h>
+#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/of_device.h>
@@ -19,6 +20,10 @@
#include <dt-bindings/memory/tegra194-mc.h>
#endif
+#define MC_SID_STREAMID_OVERRIDE_MASK GENMASK(7, 0)
+#define MC_SID_STREAMID_SECURITY_WRITE_ACCESS_DISABLED BIT(16)
+#define MC_SID_STREAMID_SECURITY_OVERRIDE BIT(8)
+
struct tegra186_mc_client {
const char *name;
unsigned int id;
@@ -1808,6 +1813,71 @@ static struct platform_driver tegra186_mc_driver = {
};
module_platform_driver(tegra186_mc_driver);
+static void tegra186_mc_client_sid_override(struct tegra_mc *mc,
+ const struct tegra186_mc_client
*client,
+ unsigned int sid)
+{
+ u32 value, old;
+
+ value = readl(mc->regs + client->regs.security);
+ if ((value & MC_SID_STREAMID_SECURITY_OVERRIDE) == 0) {
+ /*
+ * If the secure firmware has locked this down the override
+ * for this memory client, there's nothing we can do here.
+ */
+ if (value & MC_SID_STREAMID_SECURITY_WRITE_ACCESS_DISABLED)
+ return;
+
+ /*
+ * Otherwise, try to set the override itself. Typically the
+ * secure firmware will never have set this configuration.
+ * Instead, it will either have disabled write access to
+ * this field, or it will already have set an explicit
+ * override itself.
+ */
+ WARN_ON((value & MC_SID_STREAMID_SECURITY_OVERRIDE) == 0);
+
+ value |= MC_SID_STREAMID_SECURITY_OVERRIDE;
+ writel(value, mc->regs + client->regs.security);
+ }
+
+ value = readl(mc->regs + client->regs.override);
+ old = value & MC_SID_STREAMID_OVERRIDE_MASK;
+
+ if (old != sid) {
+ dev_dbg(mc->dev, "overriding SID %x for %s with %x\n", old,
+ client->name, sid);
+ writel(sid, mc->regs + client->regs.override);
+ }
+}
+
+int tegra186_mc_probe_device(struct tegra_mc *mc, struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+ struct of_phandle_args args;
+ unsigned int i, index = 0;
+
+ while (!of_parse_phandle_with_args(dev->of_node, "interconnects",
"#interconnect-cells",
+ index, &args)) {
+ if (args.np == mc->dev->of_node && args.args_count != 0) {
+ for (i = 0; i < mc->soc->num_clients; i++) {
+ const struct tegra186_mc_client *client =
&mc->soc->clients[i];
+
+ if (client->id == args.args[0]) {
+ u32 sid = fwspec->ids[0] &
MC_SID_STREAMID_OVERRIDE_MASK;
+
+ tegra186_mc_client_sid_override(mc,
client, sid);
+ }
+ }
+ }
+
+ index++;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(tegra186_mc_probe_device);
+
MODULE_AUTHOR("Thierry Reding <tred...@nvidia.com>");
MODULE_DESCRIPTION("NVIDIA Tegra186 Memory Controller driver");
MODULE_LICENSE("GPL v2");
diff --git a/include/soc/tegra/mc.h b/include/soc/tegra/mc.h
index 7be8441c6e9e..73d5ecf0e76a 100644
--- a/include/soc/tegra/mc.h
+++ b/include/soc/tegra/mc.h
@@ -168,4 +168,14 @@ devm_tegra_memory_controller_get(struct device *dev)
}
#endif
+#if IS_ENABLED(CONFIG_ARCH_TEGRA_186_SOC) || \
+ IS_ENABLED(CONFIG_ARCH_TEGRA_194_SOC)
+int tegra186_mc_probe_device(struct tegra_mc *mc, struct device *dev);
+#else
+static inline int tegra186_mc_probe_device(struct tegra_mc *mc, struct device
*dev)
+{
+ return 0;
+}
+#endif
+
#endif /* __SOC_TEGRA_MC_H__ */
--
2.30.2
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