From: Thierry Reding <treding@xxxxxxxxxx>
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 <treding@xxxxxxxxxx>
---
drivers/memory/tegra/mc.c | 9 +++++
drivers/memory/tegra/tegra186.c | 72 +++++++++++++++++++++++++++++++++
include/soc/tegra/mc.h | 3 ++
3 files changed, 84 insertions(+)
diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c
index 11b83de9361c..3c5aae7abf35 100644
--- a/drivers/memory/tegra/mc.c
+++ b/drivers/memory/tegra/mc.c
@@ -97,6 +97,15 @@ struct tegra_mc *devm_tegra_memory_controller_get(struct device *dev)
}
EXPORT_SYMBOL_GPL(devm_tegra_memory_controller_get);
+int tegra_mc_probe_device(struct tegra_mc *mc, struct device *dev)
+{
+ if (mc->soc->ops && mc->soc->ops->probe_device)
+ return mc->soc->ops->probe_device(mc, dev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(tegra_mc_probe_device);
+
static int tegra_mc_block_dma_common(struct tegra_mc *mc,
const struct tegra_mc_reset *rst)
{
diff --git a/drivers/memory/tegra/tegra186.c b/drivers/memory/tegra/tegra186.c
index 1f87915ccd62..e65eac5764d4 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>
@@ -15,6 +16,10 @@
#include <dt-bindings/memory/tegra186-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)
+
static void tegra186_mc_program_sid(struct tegra_mc *mc)
{
unsigned int i;
@@ -66,10 +71,77 @@ static int tegra186_mc_resume(struct tegra_mc *mc)
return 0;
}
+static void tegra186_mc_client_sid_override(struct tegra_mc *mc,
+ const struct tegra_mc_client *client,
+ unsigned int sid)
+{
+ u32 value, old;
+
+ value = readl(mc->regs + client->regs.sid.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.sid.security);
+ }
+
+ value = readl(mc->regs + client->regs.sid.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.sid.override);
+ }
+}
+
+static int tegra186_mc_probe_device(struct tegra_mc *mc, struct device *dev)
+{
+#if IS_ENABLED(CONFIG_IOMMU_API)
+ 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 tegra_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++;
+ }
+#endif
+
+ return 0;
+}
+
const struct tegra_mc_ops tegra186_mc_ops = {
.probe = tegra186_mc_probe,
.remove = tegra186_mc_remove,
.resume = tegra186_mc_resume,
+ .probe_device = tegra186_mc_probe_device,
};
#if defined(CONFIG_ARCH_TEGRA_186_SOC)
diff --git a/include/soc/tegra/mc.h b/include/soc/tegra/mc.h
index 1bd5aed81868..e19c2504a14b 100644
--- a/include/soc/tegra/mc.h
+++ b/include/soc/tegra/mc.h
@@ -180,6 +180,7 @@ struct tegra_mc_ops {
int (*suspend)(struct tegra_mc *mc);
int (*resume)(struct tegra_mc *mc);
irqreturn_t (*handle_irq)(int irq, void *data);
+ int (*probe_device)(struct tegra_mc *mc, struct device *dev);
};
struct tegra_mc_soc {
@@ -244,4 +245,6 @@ devm_tegra_memory_controller_get(struct device *dev)
}
#endif
+int tegra_mc_probe_device(struct tegra_mc *mc, struct device *dev);
+
#endif /* __SOC_TEGRA_MC_H__ */
--
2.31.1
