memory: tegra: Add support for a variable-size client ID bitfield

Recent versions of the Tegra MC hardware extend the size of the client
ID bitfield in the MC_ERR_STATUS register by one bit.  While one could
simply extend the bitfield for older hardware, that would allow data
from reserved bits into the driver code, which is generally a bad idea
on principle.  So this patch instead passes in the client ID mask from
from the per-SoC MC data.

There's no MC support for T210 (yet), but when that support winds up
in the kernel, the appropriate soc->client_id_mask value for that chip
will be 0xff.

Based on an original patch by David Ung <davidu@nvidia.com>.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Paul Walmsley <pwalmsley@nvidia.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: David Ung <davidu@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/memory/tegra/mc.c

@@ -42,7 +42,6 @@
 #define  MC_ERR_STATUS_ADR_HI_MASK 0x3
 #define  MC_ERR_STATUS_SECURITY (1 << 17)
 #define  MC_ERR_STATUS_RW (1 << 16)
-#define  MC_ERR_STATUS_CLIENT_MASK 0x7f
 
 #define MC_ERR_ADR 0x0c
 
@@ -283,7 +282,7 @@ static irqreturn_t tegra_mc_irq(int irq, void *data)
 		else
 			secure = "";
 
-		id = value & MC_ERR_STATUS_CLIENT_MASK;
+		id = value & mc->soc->client_id_mask;
 
 		for (i = 0; i < mc->soc->num_clients; i++) {
 			if (mc->soc->clients[i].id == id) {
@@ -410,6 +409,8 @@ static int tegra_mc_probe(struct platform_device *pdev)
 		return err;
 	}
 
+	WARN(!mc->soc->client_id_mask, "Missing client ID mask for this SoC\n");
+
 	value = MC_INT_DECERR_MTS | MC_INT_SECERR_SEC | MC_INT_DECERR_VPR |
 		MC_INT_INVALID_APB_ASID_UPDATE | MC_INT_INVALID_SMMU_PAGE |
 		MC_INT_SECURITY_VIOLATION | MC_INT_DECERR_EMEM;

drivers/memory/tegra/tegra114.c

@@ -944,5 +944,6 @@ const struct tegra_mc_soc tegra114_mc_soc = {
 	.num_clients = ARRAY_SIZE(tegra114_mc_clients),
 	.num_address_bits = 32,
 	.atom_size = 32,
+	.client_id_mask = 0x7f,
 	.smmu = &tegra114_smmu_soc,
 };

drivers/memory/tegra/tegra124.c

@@ -1032,6 +1032,7 @@ const struct tegra_mc_soc tegra124_mc_soc = {
 	.num_clients = ARRAY_SIZE(tegra124_mc_clients),
 	.num_address_bits = 34,
 	.atom_size = 32,
+	.client_id_mask = 0x7f,
 	.smmu = &tegra124_smmu_soc,
 	.emem_regs = tegra124_mc_emem_regs,
 	.num_emem_regs = ARRAY_SIZE(tegra124_mc_emem_regs),
@@ -1067,6 +1068,7 @@ const struct tegra_mc_soc tegra132_mc_soc = {
 	.num_clients = ARRAY_SIZE(tegra124_mc_clients),
 	.num_address_bits = 34,
 	.atom_size = 32,
+	.client_id_mask = 0x7f,
 	.smmu = &tegra132_smmu_soc,
 };
 #endif /* CONFIG_ARCH_TEGRA_132_SOC */

drivers/memory/tegra/tegra30.c

@@ -966,5 +966,6 @@ const struct tegra_mc_soc tegra30_mc_soc = {
 	.num_clients = ARRAY_SIZE(tegra30_mc_clients),
 	.num_address_bits = 32,
 	.atom_size = 16,
+	.client_id_mask = 0x7f,
 	.smmu = &tegra30_smmu_soc,
 };

include/soc/tegra/mc.h

@@ -102,6 +102,8 @@ struct tegra_mc_soc {
 	unsigned int num_address_bits;
 	unsigned int atom_size;
 
+	u8 client_id_mask;
+
 	const struct tegra_smmu_soc *smmu;
 };