iommu/pamu: Fix PAMU boot crash

Commit 68a17f0be6fe introduced an initialization order
problem, where devices are linked against an iommu which is
not yet initialized. Fix it by initializing the iommu-device
before the iommu-ops are registered against the bus.

Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: 68a17f0be6fe ('iommu/pamu: Add support for generic iommu-device')
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/fsl_pamu.c

@@ -44,8 +44,6 @@ static struct paace *spaact;
 
 static bool probed;			/* Has PAMU been probed? */
 
-struct iommu_device pamu_iommu;	/* IOMMU core code handle */
-
 /*
  * Table for matching compatible strings, for device tree
  * guts node, for QorIQ SOCs.
@@ -1156,18 +1154,6 @@ static int fsl_pamu_probe(struct platform_device *pdev)
 	if (ret)
 		goto error_genpool;
 
-	ret = iommu_device_sysfs_add(&pamu_iommu, dev, NULL, "iommu0");
-	if (ret)
-		goto error_genpool;
-
-	iommu_device_set_ops(&pamu_iommu, &fsl_pamu_ops);
-
-	ret = iommu_device_register(&pamu_iommu);
-	if (ret) {
-		dev_err(dev, "Can't register iommu device\n");
-		goto error_sysfs;
-	}
-
 	pamubypenr = in_be32(&guts_regs->pamubypenr);
 
 	for (pamu_reg_off = 0, pamu_counter = 0x80000000; pamu_reg_off < size;
@@ -1195,9 +1181,6 @@ static int fsl_pamu_probe(struct platform_device *pdev)
 
 	return 0;
 
-error_sysfs:
-	iommu_device_sysfs_remove(&pamu_iommu);
-
 error_genpool:
 	gen_pool_destroy(spaace_pool);
 

drivers/iommu/fsl_pamu.h

@@ -391,9 +391,6 @@ struct ome {
 #define EOE_WWSAOL      0x1e    /* Write with stash allocate only and lock */
 #define EOE_VALID       0x80
 
-extern const struct iommu_ops fsl_pamu_ops;
-extern struct iommu_device pamu_iommu;	/* IOMMU core code handle */
-
 /* Function prototypes */
 int pamu_domain_init(void);
 int pamu_enable_liodn(int liodn);

drivers/iommu/fsl_pamu_domain.c

@@ -33,6 +33,8 @@ static struct kmem_cache *fsl_pamu_domain_cache;
 static struct kmem_cache *iommu_devinfo_cache;
 static DEFINE_SPINLOCK(device_domain_lock);
 
+struct iommu_device pamu_iommu;	/* IOMMU core code handle */
+
 static struct fsl_dma_domain *to_fsl_dma_domain(struct iommu_domain *dom)
 {
 	return container_of(dom, struct fsl_dma_domain, iommu_domain);
@@ -1050,7 +1052,7 @@ static u32 fsl_pamu_get_windows(struct iommu_domain *domain)
 	return dma_domain->win_cnt;
 }
 
-const struct iommu_ops fsl_pamu_ops = {
+static const struct iommu_ops fsl_pamu_ops = {
 	.capable	= fsl_pamu_capable,
 	.domain_alloc	= fsl_pamu_domain_alloc,
 	.domain_free    = fsl_pamu_domain_free,
@@ -1076,6 +1078,19 @@ int __init pamu_domain_init(void)
 	if (ret)
 		return ret;
 
+	ret = iommu_device_sysfs_add(&pamu_iommu, NULL, NULL, "iommu0");
+	if (ret)
+		return ret;
+
+	iommu_device_set_ops(&pamu_iommu, &fsl_pamu_ops);
+
+	ret = iommu_device_register(&pamu_iommu);
+	if (ret) {
+		iommu_device_sysfs_remove(&pamu_iommu);
+		pr_err("Can't register iommu device\n");
+		return ret;
+	}
+
 	bus_set_iommu(&platform_bus_type, &fsl_pamu_ops);
 	bus_set_iommu(&pci_bus_type, &fsl_pamu_ops);
 

drivers/iommu/fsl_pamu_domain.h

@@ -21,8 +21,6 @@
 
 #include "fsl_pamu.h"
 
-const struct iommu_ops fsl_pamu_ops;
-
 struct dma_window {
 	phys_addr_t paddr;
 	u64 size;