[PATCH 6.1 0052/1146] soc/tegra: cbb: Check firewall before enabling error reporting

Greg Kroah-Hartman
2022-12-28T15:04:31Z

From: Sumit Gupta <sumitg@nvidia.com>

[ Upstream commit 2927cf85f4877f417f884919de8e04ab9b362d32 ]

To enable error reporting for a fabric to CCPLEX, we need to write its
register for enabling error interrupt to CCPLEX during boot and later
clear the error status register after error occurs. If a fabric's
registers are protected and not accessible from CCPLEX, then accessing
the registers will cause CBB firewall error.

Add support to check whether write access from CCPLEX to the registers
of a fabric is not blocked by it's firewall before enabling error
reporting to CCPLEX for that fabric.

Fixes: fc2f151d2314 ("soc/tegra: cbb: Add driver for Tegra234 CBB 2.0")
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/soc/tegra/cbb/tegra234-cbb.c | 83 +++++++++++++++++++++++++++-
1 file changed, 81 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/tegra/cbb/tegra234-cbb.c b/drivers/soc/tegra/cbb/tegra234-cbb.c
index 0fab9e21d677..f33d094e5ea6 100644
--- a/drivers/soc/tegra/cbb/tegra234-cbb.c
+++ b/drivers/soc/tegra/cbb/tegra234-cbb.c
@@ -72,6 +72,11 @@

#define REQ_SOCKET_ID GENMASK(27, 24)

+#define CCPLEX_MSTRID 0x1
+#define FIREWALL_APERTURE_SZ 0x10000
+/* Write firewall check enable */
+#define WEN 0x20000
+
enum tegra234_cbb_fabric_ids {
CBB_FAB_ID,
SCE_FAB_ID,
@@ -92,6 +97,9 @@ struct tegra234_slave_lookup {
struct tegra234_cbb_fabric {
const char *name;
phys_addr_t off_mask_erd;
+ phys_addr_t firewall_base;
+ unsigned int firewall_ctl;
+ unsigned int firewall_wr_ctl;
const char * const *master_id;
unsigned int notifier_offset;
const struct tegra_cbb_error *errors;
@@ -129,6 +137,44 @@ static inline struct tegra234_cbb *to_tegra234_cbb(struct tegra_cbb *cbb)
static LIST_HEAD(cbb_list);
static DEFINE_SPINLOCK(cbb_lock);

+static bool
+tegra234_cbb_write_access_allowed(struct platform_device *pdev, struct tegra234_cbb *cbb)
+{
+ u32 val;
+
+ if (!cbb->fabric->firewall_base ||
+ !cbb->fabric->firewall_ctl ||
+ !cbb->fabric->firewall_wr_ctl) {
+ dev_info(&pdev->dev, "SoC data missing for firewall\n");
+ return false;
+ }
+
+ if ((cbb->fabric->firewall_ctl > FIREWALL_APERTURE_SZ) ||
+ (cbb->fabric->firewall_wr_ctl > FIREWALL_APERTURE_SZ)) {
+ dev_err(&pdev->dev, "wrong firewall offset value\n");
+ return false;
+ }
+
+ val = readl(cbb->regs + cbb->fabric->firewall_base + cbb->fabric->firewall_ctl);
+ /*
+ * If the firewall check feature for allowing or blocking the
+ * write accesses through the firewall of a fabric is disabled
+ * then CCPLEX can write to the registers of that fabric.
+ */
+ if (!(val & WEN))
+ return true;
+
+ /*
+ * If the firewall check is enabled then check whether CCPLEX
+ * has write access to the fabric's error notifier registers
+ */
+ val = readl(cbb->regs + cbb->fabric->firewall_base + cbb->fabric->firewall_wr_ctl);
+ if (val & (BIT(CCPLEX_MSTRID)))
+ return true;
+
+ return false;
+}
+
static void tegra234_cbb_fault_enable(struct tegra_cbb *cbb)
{
struct tegra234_cbb *priv = to_tegra234_cbb(cbb);
@@ -551,7 +597,7 @@ static irqreturn_t tegra234_cbb_isr(int irq, void *data)
*/
if (priv->fabric->off_mask_erd) {
mstr_id = FIELD_GET(USRBITS_MSTR_ID, priv->mn_user_bits);
- if (mstr_id == 0x1)
+ if (mstr_id == CCPLEX_MSTRID)
is_inband_err = 1;
}
}
@@ -665,6 +711,9 @@ static const struct tegra234_cbb_fabric tegra234_aon_fabric = {
.errors = tegra234_cbb_errors,
.max_errors = ARRAY_SIZE(tegra234_cbb_errors),
.notifier_offset = 0x17000,
+ .firewall_base = 0x30000,
+ .firewall_ctl = 0x8d0,
+ .firewall_wr_ctl = 0x8c8,
};

static const struct tegra234_slave_lookup tegra234_bpmp_slave_map[] = {
@@ -683,6 +732,9 @@ static const struct tegra234_cbb_fabric tegra234_bpmp_fabric = {
.errors = tegra234_cbb_errors,
.max_errors = ARRAY_SIZE(tegra234_cbb_errors),
.notifier_offset = 0x19000,
+ .firewall_base = 0x30000,
+ .firewall_ctl = 0x8f0,
+ .firewall_wr_ctl = 0x8e8,
};

static const struct tegra234_slave_lookup tegra234_cbb_slave_map[] = {
@@ -757,7 +809,10 @@ static const struct tegra234_cbb_fabric tegra234_cbb_fabric = {
.errors = tegra234_cbb_errors,
.max_errors = ARRAY_SIZE(tegra234_cbb_errors),
.notifier_offset = 0x60000,
- .off_mask_erd = 0x3a004
+ .off_mask_erd = 0x3a004,
+ .firewall_base = 0x10000,
+ .firewall_ctl = 0x23f0,
+ .firewall_wr_ctl = 0x23e8,
};

static const struct tegra234_slave_lookup tegra234_common_slave_map[] = {
@@ -777,6 +832,9 @@ static const struct tegra234_cbb_fabric tegra234_dce_fabric = {
.errors = tegra234_cbb_errors,
.max_errors = ARRAY_SIZE(tegra234_cbb_errors),
.notifier_offset = 0x19000,
+ .firewall_base = 0x30000,
+ .firewall_ctl = 0x290,
+ .firewall_wr_ctl = 0x288,
};

static const struct tegra234_cbb_fabric tegra234_rce_fabric = {
@@ -787,6 +845,9 @@ static const struct tegra234_cbb_fabric tegra234_rce_fabric = {
.errors = tegra234_cbb_errors,
.max_errors = ARRAY_SIZE(tegra234_cbb_errors),
.notifier_offset = 0x19000,
+ .firewall_base = 0x30000,
+ .firewall_ctl = 0x290,
+ .firewall_wr_ctl = 0x288,
};

static const struct tegra234_cbb_fabric tegra234_sce_fabric = {
@@ -797,6 +858,9 @@ static const struct tegra234_cbb_fabric tegra234_sce_fabric = {
.errors = tegra234_cbb_errors,
.max_errors = ARRAY_SIZE(tegra234_cbb_errors),
.notifier_offset = 0x19000,
+ .firewall_base = 0x30000,
+ .firewall_ctl = 0x290,
+ .firewall_wr_ctl = 0x288,
};

static const char * const tegra241_master_id[] = {
@@ -979,6 +1043,9 @@ static const struct tegra234_cbb_fabric tegra241_cbb_fabric = {
.max_errors = ARRAY_SIZE(tegra241_cbb_errors),
.notifier_offset = 0x60000,
.off_mask_erd = 0x40004,
+ .firewall_base = 0x20000,
+ .firewall_ctl = 0x2370,
+ .firewall_wr_ctl = 0x2368,
};

static const struct tegra234_slave_lookup tegra241_bpmp_slave_map[] = {
@@ -1000,6 +1067,9 @@ static const struct tegra234_cbb_fabric tegra241_bpmp_fabric = {
.errors = tegra241_cbb_errors,
.max_errors = ARRAY_SIZE(tegra241_cbb_errors),
.notifier_offset = 0x19000,
+ .firewall_base = 0x30000,
+ .firewall_ctl = 0x8f0,
+ .firewall_wr_ctl = 0x8e8,
};

static const struct of_device_id tegra234_cbb_dt_ids[] = {
@@ -1084,6 +1154,15 @@ static int tegra234_cbb_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, cbb);

+ /*
+ * Don't enable error reporting for a Fabric if write to it's registers
+ * is blocked by CBB firewall.
+ */
+ if (!tegra234_cbb_write_access_allowed(pdev, cbb)) {
+ dev_info(&pdev->dev, "error reporting not enabled due to firewall\n");
+ return 0;
+ }
+
spin_lock_irqsave(&cbb_lock, flags);
list_add(&cbb->base.node, &cbb_list);
spin_unlock_irqrestore(&cbb_lock, flags);
--
2.35.1