[PATCH v3 23/26] crypto: rockchip: Check for maximum frequency of clocks

[Corentin Labbe <clabbe@baylibre.com>]

Rockchip's datasheet give maximum frequencies for some clocks, so add
checks for verifying they are within limits.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
---
 drivers/crypto/rockchip/rk3288_crypto.c | 57 +++++++++++++++++++++----
 drivers/crypto/rockchip/rk3288_crypto.h |  9 ++++
 2 files changed, 57 insertions(+), 9 deletions(-)

diff --git a/drivers/crypto/rockchip/rk3288_crypto.c b/drivers/crypto/rockchip/rk3288_crypto.c
index bb1adbe947f9..ededae9f2671 100644
--- a/drivers/crypto/rockchip/rk3288_crypto.c
+++ b/drivers/crypto/rockchip/rk3288_crypto.c
@@ -21,16 +21,58 @@
 
 static const struct rk_variant rk3328_variant = {
 	.num_instance = 1,
+	.num_clks = 3,
 };
 
 static const struct rk_variant rk3288_variant = {
-	.num_instance = 1
+	.num_instance = 1,
+	.num_clks = 3,
+	.rkclks = {
+		{ "sclk", 150000000},
+	}
 };
 
 static const struct rk_variant rk3399_variant = {
-	.num_instance = 2
+	.num_instance = 2,
+	.num_clks = 6,
 };
 
+static int rk_crypto_get_clks(struct rk_crypto_info *dev)
+{
+	int i, j, err;
+	unsigned long cr;
+
+	dev->num_clks = devm_clk_bulk_get_all(dev->dev, &dev->clks);
+	if (dev->num_clks < dev->variant->num_clks) {
+		dev_err(dev->dev, "Missing clocks, got %d instead of %d\n",
+			dev->num_clks, dev->variant->num_clks);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < dev->num_clks; i++) {
+		cr = clk_get_rate(dev->clks[i].clk);
+		for (j = 0; j < ARRAY_SIZE(dev->variant->rkclks); j++) {
+			if (dev->variant->rkclks[j].max == 0)
+				continue;
+			if (strcmp(dev->variant->rkclks[j].name, dev->clks[i].id))
+				continue;
+			if (cr > dev->variant->rkclks[j].max) {
+				err = clk_set_rate(dev->clks[i].clk,
+						   dev->variant->rkclks[j].max);
+				if (err)
+					dev_err(dev->dev, "Fail downclocking %s from %lu to %lu\n",
+						dev->variant->rkclks[j].name, cr,
+						dev->variant->rkclks[j].max);
+				else
+					dev_info(dev->dev, "Downclocking %s from %lu to %lu\n",
+						 dev->variant->rkclks[j].name, cr,
+						 dev->variant->rkclks[j].max);
+			}
+		}
+	}
+	return 0;
+}
+
 static int rk_crypto_enable_clk(struct rk_crypto_info *dev)
 {
 	int err;
@@ -281,16 +323,13 @@ static int rk_crypto_probe(struct platform_device *pdev)
 		goto err_crypto;
 	}
 
-	crypto_info->num_clks = devm_clk_bulk_get_all(&pdev->dev,
-			&crypto_info->clks);
-	if (crypto_info->num_clks < 3) {
-		err = -EINVAL;
-		goto err_crypto;
-	}
-
 	crypto_info->dev = &pdev->dev;
 	platform_set_drvdata(pdev, crypto_info);
 
+	err = rk_crypto_get_clks(crypto_info);
+	if (err)
+		goto err_crypto;
+
 	err = rk_crypto_pm_init(crypto_info);
 	if (err)
 		goto err_pm;
diff --git a/drivers/crypto/rockchip/rk3288_crypto.h b/drivers/crypto/rockchip/rk3288_crypto.h
index e1dac351bc64..8fd46cda5189 100644
--- a/drivers/crypto/rockchip/rk3288_crypto.h
+++ b/drivers/crypto/rockchip/rk3288_crypto.h
@@ -183,8 +183,17 @@
 #define RK_CRYPTO_HASH_DOUT_6		0x01a4
 #define RK_CRYPTO_HASH_DOUT_7		0x01a8
 
+#define RK_MAX_CLKS 6
+
+struct rk_clks {
+	const char *name;
+	unsigned long max;
+};
+
 struct rk_variant {
 	int num_instance;
+	int num_clks;
+	struct rk_clks rkclks[RK_MAX_CLKS];
 };
 
 struct rk_instance {
-- 
2.34.1