Commit 393d66fd authored by Thierry Reding's avatar Thierry Reding Committed by Krzysztof Kozlowski
Browse files

memory: tegra: Implement SID override programming 



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: default avatarThierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20210603164632.1000458-2-thierry.reding@gmail.com


Signed-off-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
parent 8fd9f632

drivers/memory/tegra/mc.c

+9 −0
Original line number Diff line number Diff line
@@ -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)

{

drivers/memory/tegra/tegra186.c

+72 −0
Original line number Diff line number Diff line
@@ -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)

include/soc/tegra/mc.h

+3 −0
Original line number Diff line number Diff line
@@ -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__ */