Skip to contentSkip to conversation

memory: tegra: Add SID override programming for MC clients

PATCH Applied Ashish Mhetre 2 participants 3 messages Nov 7, 2023 – Nov 21, 2023

Subsystems (2)
Tegra architecture support Memory controller drivers
lore
Share & tools
lore

Ashish Mhetre

author
#0 lore raw

PATCH v2 1/2 memory: tegra: Add SID override programming for MC clients

For some devices the bootloader/firmware may set up the device in bypass. Memory clients like display needs kernel to program SID after resume because bootloader/firmware programs the SID of display device to bypass. In order to make sure that kernel IOMMU mappings for these devices work after resume, add SID override programming support for all memory clients on memory controller resume.

This partially reverts 'commit ef86b2c2807f ("memory: tegra: Remove clients SID override programming")'

Signed-off-by Ashish Mhetre <[email protected]>

---
Changes in v2:
- Fixed build issues reported by Kernel test robot from v1

 drivers/memory/tegra/tegra186.c | 14 ++++++++++++++
 include/soc/tegra/mc.h          |  1 +
 2 files changed, 15 insertions(+)
drivers/memory/tegra/tegra186.c +14 -0
index 533f85a4b2bd..8203f0db1350 100644
@@ -136,9 +136,23 @@ static int tegra186_mc_probe_device(struct tegra_mc *mc, struct device *dev)
 	return 0;
 }
 
+static int tegra186_mc_resume(struct tegra_mc *mc)
+{
+	unsigned int i;
+
+	for (i = 0; i < mc->soc->num_clients; i++) {
+		const struct tegra_mc_client *client = &mc->soc->clients[i];
+
+		tegra186_mc_client_sid_override(mc, client, client->sid);
+	}
+
+	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,
 	.handle_irq = tegra30_mc_handle_irq,
 };
include/soc/tegra/mc.h +1 -0
index 71ae37d3bedd..af1d73a7f0cd 100644
@@ -162,6 +162,7 @@ struct tegra_mc_ops {
 	 */
 	int (*probe)(struct tegra_mc *mc);
 	void (*remove)(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);
 };
Signature · 1 line
2.17.1
author
#1 lore raw

PATCH v2 2/2 memory: tegra: Skip SID programming if SID registers aren't set

There are few MC clients where SID security and override register offsets are not specified like "sw_cluster0" in tegra234. Don't program SID override for such clients because it leads to access to invalid addresses.

Signed-off-by Ashish Mhetre <[email protected]>
---
 drivers/memory/tegra/tegra186.c | 3 +++
 1 file changed, 3 insertions(+)
drivers/memory/tegra/tegra186.c +3 -0
index 8203f0db1350..d1f1dfb42716 100644
@@ -75,6 +75,9 @@ static void tegra186_mc_client_sid_override(struct tegra_mc *mc,
 {
 	u32 value, old;
 
+	if (client->regs.sid.security == 0 && client->regs.sid.override == 0)
+		return;
+
 	value = readl(mc->regs + client->regs.sid.security);
 	if ((value & MC_SID_STREAMID_SECURITY_OVERRIDE) == 0) {
 		/*
Signature · 1 line
2.17.1
Applied
#2 lore raw
In reply to Ashish Mhetre
Quoted 8 lines · Ashish Mhetre

For some devices the bootloader/firmware may set up the device in bypass. Memory clients like display needs kernel to program SID after resume because bootloader/firmware programs the SID of display device to bypass. In order to make sure that kernel IOMMU mappings for these devices work after resume, add SID override programming support for all memory clients on memory controller resume.

[...]

Applied, thanks!

[1/2] memory: tegra: Add SID override programming for MC clients

      https://git.kernel.org/krzk/linux-mem-ctrl/c/fe3b082a6eb8b1526ed7397c849d6b2a6baeb6a1
[2/2] memory: tegra: Skip SID programming if SID registers aren't set
      https://git.kernel.org/krzk/linux-mem-ctrl/c/0d6c918011ce4764ed277de4726a468b7ffe5fed

Best regards,

Signature · 1 line
Krzysztof Kozlowski <[email protected]>