[PATCH v2 27/29] iommu/mediatek: Initialise/Remove for multi bank dev

Yong Wu yong.wu at mediatek.com
Thu Aug 12 23:53:22 PDT 2021


The registers for each bank of the IOMMU base are in order, delta is
0x1000. Initialise the base for each bank.

For all the previous SoC, we only have bank0. thus use "do {} while()"
to allow bank0 always go.

When removing the device, Not always all the banks are initialised, it
depend on if there is masters for some banks. thus, use a register to
confirm this.

Signed-off-by: Yong Wu <yong.wu at mediatek.com>
---
 drivers/iommu/mtk_iommu.c | 51 +++++++++++++++++++++++++++++----------
 1 file changed, 38 insertions(+), 13 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index ce83569eec21..142ee8f3a560 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -113,6 +113,7 @@
 #define F_MMU_INT_ID_PORT_ID(a)			(((a) >> 2) & 0x1f)
 
 #define MTK_PROTECT_PA_ALIGN			256
+#define MTK_IOMMU_BANK_SZ			0x1000
 
 #define PERICFG_IOMMU_1				0x714
 
@@ -945,11 +946,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
 	struct mtk_iommu_data   *data;
 	struct device           *dev = &pdev->dev;
 	struct resource         *res;
-	resource_size_t		ioaddr;
+	resource_size_t		ioaddr, size;
 	struct component_match  *match = NULL;
 	struct regmap		*infracfg;
 	void                    *protect;
-	int                     ret;
+	int                     ret, i = 0;
 	u32			val;
 	char                    *p;
 	struct mtk_iommu_bank_data *bank;
@@ -991,20 +992,31 @@ static int mtk_iommu_probe(struct platform_device *pdev)
 	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	size = resource_size(res);
+	if (size < data->plat_data->bank_nr * MTK_IOMMU_BANK_SZ) {
+		dev_err(dev, "banknr %d. res %pR is not enough.\n",
+			data->plat_data->bank_nr, res);
+		return -EINVAL;
+	}
 	base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 	ioaddr = res->start;
 
-	bank = &data->bank[0];
-	bank->id = 0;
-	bank->base = base;
-	bank->irq = platform_get_irq(pdev, 0);
-	if (bank->irq < 0)
-		return bank->irq;
-	bank->pdev = dev;
-	bank->pdata = data;
-	spin_lock_init(&bank->tlb_lock);
+	do {
+		if (!data->plat_data->bank_enable[i])
+			continue;
+		bank = &data->bank[i];
+		bank->id = i;
+		bank->base = base + i * MTK_IOMMU_BANK_SZ;
+
+		bank->irq = platform_get_irq(pdev, i);
+		if (bank->irq < 0)
+			return bank->irq;
+		bank->pdev = dev;
+		bank->pdata = data;
+		spin_lock_init(&bank->tlb_lock);
+	} while (++i < data->plat_data->bank_nr);
 
 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_BCLK)) {
 		data->bclk = devm_clk_get(dev, "bclk");
@@ -1089,7 +1101,9 @@ static int mtk_iommu_probe(struct platform_device *pdev)
 static int mtk_iommu_remove(struct platform_device *pdev)
 {
 	struct mtk_iommu_data *data = platform_get_drvdata(pdev);
-	struct mtk_iommu_bank_data *bank = &data->bank[0];
+	struct mtk_iommu_bank_data *bank;
+	bool bank_hwinit;
+	int i;
 
 	iommu_device_sysfs_remove(&data->iommu);
 	iommu_device_unregister(&data->iommu);
@@ -1101,7 +1115,18 @@ static int mtk_iommu_remove(struct platform_device *pdev)
 	if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_MM))
 		device_link_remove(data->smicomm_dev, &pdev->dev);
 	pm_runtime_disable(&pdev->dev);
-	devm_free_irq(&pdev->dev, bank->irq, bank);
+	for (i = 0; i < data->plat_data->bank_nr; i++) {
+		bank = &data->bank[i];
+		/*
+		 * Use a register value to confirm if this bank HW is initialised.
+		 * If the bank has no consumer, the bank HW still won't be
+		 * initialised even though bank_enable is true.
+		 */
+		bank_hwinit = !!readl_relaxed(bank->base + REG_MMU_PT_BASE_ADDR);
+		if (!bank_hwinit)
+			continue;
+		devm_free_irq(&pdev->dev, bank->irq, bank);
+	}
 	component_master_del(&pdev->dev, &mtk_iommu_com_ops);
 	return 0;
 }
-- 
2.18.0


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