msm: iommu: Remove dependency on IDR

Remove the depencency on the IOMMU IDR register, as it may
not be accessible depending on the security configuraton.
This involves moving the NCB field of IDR into the platform
data.

Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>

4 files changed, 42 insertions, 22 deletions

diff --git a/arch/arm/mach-msm/devices-iommu.c b/arch/arm/mach-msm/devices-iommu.c
index af97afe..24030d0 100644
--- a/arch/arm/mach-msm/devices-iommu.c
+++ b/arch/arm/mach-msm/devices-iommu.c
@@ -280,50 +280,62 @@ static struct platform_device msm_root_iommu_dev = {
 
 static struct msm_iommu_dev jpegd_iommu = {
 	.name = "jpegd",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev vpe_iommu = {
-	.name = "vpe"
+	.name = "vpe",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev mdp0_iommu = {
-	.name = "mdp0"
+	.name = "mdp0",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev mdp1_iommu = {
-	.name = "mdp1"
+	.name = "mdp1",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev rot_iommu = {
-	.name = "rot"
+	.name = "rot",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev ijpeg_iommu = {
-	.name = "ijpeg"
+	.name = "ijpeg",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev vfe_iommu = {
 	.name = "vfe",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev vcodec_a_iommu = {
-	.name = "vcodec_a"
+	.name = "vcodec_a",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev vcodec_b_iommu = {
-	.name = "vcodec_b"
+	.name = "vcodec_b",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev gfx3d_iommu = {
 	.name = "gfx3d",
+	.ncb = 3,
 };
 
 static struct msm_iommu_dev gfx2d0_iommu = {
 	.name = "gfx2d0",
+	.ncb = 2,
 };
 
 static struct msm_iommu_dev gfx2d1_iommu = {
 	.name = "gfx2d1",
+	.ncb = 2,
 };
 
 static struct platform_device msm_device_iommu_jpegd = {
diff --git a/arch/arm/mach-msm/include/mach/iommu.h b/arch/arm/mach-msm/include/mach/iommu.h
index 4dfe7ef..5c7c955 100644
--- a/arch/arm/mach-msm/include/mach/iommu.h
+++ b/arch/arm/mach-msm/include/mach/iommu.h
@@ -45,9 +45,11 @@
 /**
  * struct msm_iommu_dev - a single IOMMU hardware instance
  * name		Human-readable name given to this IOMMU HW instance
+ * ncb		Number of context banks present on this IOMMU HW instance
  */
 struct msm_iommu_dev {
 	const char *name;
+	int ncb;
 };
 
 /**
@@ -69,6 +71,7 @@ struct msm_iommu_ctx_dev {
 /**
  * struct msm_iommu_drvdata - A single IOMMU hardware instance
  * @base:	IOMMU config port base address (VA)
+ * @ncb		The number of contexts on this IOMMU
  * @irq:	Interrupt number
  * @clk:	The bus clock for this IOMMU hardware instance
  * @pclk:	The clock for the IOMMU bus interconnect
@@ -79,6 +82,7 @@ struct msm_iommu_ctx_dev {
 struct msm_iommu_drvdata {
 	void __iomem *base;
 	int irq;
+	int ncb;
 	struct clk *clk;
 	struct clk *pclk;
 };
diff --git a/arch/arm/mach-msm/iommu.c b/arch/arm/mach-msm/iommu.c
index 9c08740..0146f519 100644
--- a/arch/arm/mach-msm/iommu.c
+++ b/arch/arm/mach-msm/iommu.c
@@ -636,7 +636,7 @@ irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
 	struct msm_iommu_drvdata *drvdata = dev_id;
 	void __iomem *base;
 	unsigned int fsr;
-	int ncb, i, ret;
+	int i, ret;
 
 	spin_lock(&msm_iommu_lock);
 
@@ -654,8 +654,7 @@ irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
 	if (ret)
 		goto fail;
 
-	ncb = GET_NCB(base)+1;
-	for (i = 0; i < ncb; i++) {
+	for (i = 0; i < drvdata->ncb; i++) {
 		fsr = GET_FSR(base, i);
 		if (fsr) {
 			pr_err("Fault occurred in context %d.\n", i);
diff --git a/arch/arm/mach-msm/iommu_dev.c b/arch/arm/mach-msm/iommu_dev.c
index 0e240c9..8e8fb07 100644
--- a/arch/arm/mach-msm/iommu_dev.c
+++ b/arch/arm/mach-msm/iommu_dev.c
@@ -85,9 +85,9 @@ fail:
 }
 EXPORT_SYMBOL(msm_iommu_get_ctx);
 
-static void msm_iommu_reset(void __iomem *base)
+static void msm_iommu_reset(void __iomem *base, int ncb)
 {
-	int ctx, ncb;
+	int ctx;
 
 	SET_RPUE(base, 0);
 	SET_RPUEIE(base, 0);
@@ -100,7 +100,6 @@ static void msm_iommu_reset(void __iomem *base)
 	SET_GLOBAL_TLBIALL(base, 0);
 	SET_RPU_ACR(base, 0);
 	SET_TLBLKCRWE(base, 1);
-	ncb = GET_NCB(base)+1;
 
 	for (ctx = 0; ctx < ncb; ctx++) {
 		SET_BPRCOSH(base, ctx, 0);
@@ -136,7 +135,7 @@ static int msm_iommu_probe(struct platform_device *pdev)
 	struct msm_iommu_dev *iommu_dev = pdev->dev.platform_data;
 	void __iomem *regs_base;
 	resource_size_t	len;
-	int ret, ncb, nm2v, irq;
+	int ret, irq, par;
 
 	if (pdev->id == -1) {
 		msm_iommu_root_dev = pdev;
@@ -211,10 +210,18 @@ static int msm_iommu_probe(struct platform_device *pdev)
 		goto fail_io;
 	}
 
-	mb();
+	msm_iommu_reset(regs_base, iommu_dev->ncb);
 
-	if (GET_IDR(regs_base) == 0) {
-		pr_err("Invalid IDR value detected\n");
+	SET_M(regs_base, 0, 1);
+	SET_PAR(regs_base, 0, 0);
+	SET_V2PCFG(regs_base, 0, 1);
+	SET_V2PPR(regs_base, 0, 0);
+	par = GET_PAR(regs_base, 0);
+	SET_V2PCFG(regs_base, 0, 0);
+	SET_M(regs_base, 0, 0);
+
+	if (!par) {
+		pr_err("%s: Invalid PAR value detected\n", iommu_dev->name);
 		ret = -ENODEV;
 		goto fail_io;
 	}
@@ -226,17 +233,15 @@ static int msm_iommu_probe(struct platform_device *pdev)
 		goto fail_io;
 	}
 
-	msm_iommu_reset(regs_base);
+
 	drvdata->pclk = iommu_pclk;
 	drvdata->clk = iommu_clk;
 	drvdata->base = regs_base;
 	drvdata->irq = irq;
-
-	nm2v = GET_NM2VCBMT((unsigned long) regs_base);
-	ncb = GET_NCB((unsigned long) regs_base);
+	drvdata->ncb = iommu_dev->ncb;
 
 	pr_info("device %s mapped at %p, irq %d with %d ctx banks\n",
-			iommu_dev->name, regs_base, irq, ncb+1);
+		iommu_dev->name, regs_base, irq, iommu_dev->ncb);
 
 	platform_set_drvdata(pdev, drvdata);