SYSMMU on some SoCs reports bogus values in VERSION register. Force
hardware version to 1.0 for such controllers. This patch also moves reading
version register to driver's probe() function.

Signed-off-by: Marek Szyprowski <m.szyprow...@samsung.com>
---
 drivers/iommu/exynos-iommu.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index e42a76cc9674..8e289e2a05fb 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -284,6 +284,28 @@ static void __sysmmu_set_ptbase(struct sysmmu_drvdata 
*data, phys_addr_t pgd)
        __sysmmu_tlb_invalidate(data);
 }
 
+static void __sysmmu_get_version(struct sysmmu_drvdata *data)
+{
+       u32 ver;
+
+       clk_enable(data->clk_master);
+       clk_enable(data->clk);
+
+       ver = __raw_readl(data->sfrbase + REG_MMU_VERSION);
+
+       /* controllers on some SoCs don't report proper version */
+       if (ver == 0x80000001u)
+               data->version = MAKE_MMU_VER(1, 0);
+       else
+               data->version = MMU_RAW_VER(ver);
+
+       dev_dbg(data->sysmmu, "hardware version: %d.%d\n",
+               MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version));
+
+       clk_disable(data->clk);
+       clk_disable(data->clk_master);
+}
+
 static void show_fault_information(struct sysmmu_drvdata *data,
                                   const struct sysmmu_fault_info *finfo,
                                   sysmmu_iova_t fault_addr)
@@ -385,7 +407,6 @@ static void __sysmmu_init_config(struct sysmmu_drvdata 
*data)
 {
        unsigned int cfg;
 
-       data->version = MMU_RAW_VER(__raw_readl(data->sfrbase + 
REG_MMU_VERSION));
        if (data->version <= MAKE_MMU_VER(3, 1))
                cfg = CFG_LRU | CFG_QOS(15);
        else if (data->version <= MAKE_MMU_VER(3, 2))
@@ -551,6 +572,7 @@ static int __init exynos_sysmmu_probe(struct 
platform_device *pdev)
 
        platform_set_drvdata(pdev, data);
 
+       __sysmmu_get_version(data);
        pm_runtime_enable(dev);
 
        return 0;
-- 
1.9.2

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