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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/crypto/allwinner/sun8i-ce/sun8i-ce-trng.c
parentInitial commit. (diff)
downloadlinux-430c2fc249ea5c0536abd21c23382884005c9093.tar.xz
linux-430c2fc249ea5c0536abd21c23382884005c9093.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/crypto/allwinner/sun8i-ce/sun8i-ce-trng.c')
-rw-r--r--drivers/crypto/allwinner/sun8i-ce/sun8i-ce-trng.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-trng.c b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-trng.c
new file mode 100644
index 000000000..5b7af4498
--- /dev/null
+++ b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-trng.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * sun8i-ce-trng.c - hardware cryptographic offloader for
+ * Allwinner H3/A64/H5/H2+/H6/R40 SoC
+ *
+ * Copyright (C) 2015-2020 Corentin Labbe <clabbe@baylibre.com>
+ *
+ * This file handle the TRNG
+ *
+ * You could find a link for the datasheet in Documentation/arm/sunxi.rst
+ */
+#include "sun8i-ce.h"
+#include <linux/dma-mapping.h>
+#include <linux/pm_runtime.h>
+#include <linux/hw_random.h>
+/*
+ * Note that according to the algorithm ID, 2 versions of the TRNG exists,
+ * The first present in H3/H5/R40/A64 and the second present in H6.
+ * This file adds support for both, but only the second is working
+ * reliabily according to rngtest.
+ **/
+
+static int sun8i_ce_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+ struct sun8i_ce_dev *ce;
+ dma_addr_t dma_dst;
+ int err = 0;
+ int flow = 3;
+ unsigned int todo;
+ struct sun8i_ce_flow *chan;
+ struct ce_task *cet;
+ u32 common;
+ void *d;
+
+ ce = container_of(rng, struct sun8i_ce_dev, trng);
+
+ /* round the data length to a multiple of 32*/
+ todo = max + 32;
+ todo -= todo % 32;
+
+ d = kzalloc(todo, GFP_KERNEL | GFP_DMA);
+ if (!d)
+ return -ENOMEM;
+
+#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG
+ ce->hwrng_stat_req++;
+ ce->hwrng_stat_bytes += todo;
+#endif
+
+ dma_dst = dma_map_single(ce->dev, d, todo, DMA_FROM_DEVICE);
+ if (dma_mapping_error(ce->dev, dma_dst)) {
+ dev_err(ce->dev, "Cannot DMA MAP DST\n");
+ err = -EFAULT;
+ goto err_dst;
+ }
+
+ err = pm_runtime_get_sync(ce->dev);
+ if (err < 0) {
+ pm_runtime_put_noidle(ce->dev);
+ goto err_pm;
+ }
+
+ mutex_lock(&ce->rnglock);
+ chan = &ce->chanlist[flow];
+
+ cet = &chan->tl[0];
+ memset(cet, 0, sizeof(struct ce_task));
+
+ cet->t_id = cpu_to_le32(flow);
+ common = ce->variant->trng | CE_COMM_INT;
+ cet->t_common_ctl = cpu_to_le32(common);
+
+ /* recent CE (H6) need length in bytes, in word otherwise */
+ if (ce->variant->trng_t_dlen_in_bytes)
+ cet->t_dlen = cpu_to_le32(todo);
+ else
+ cet->t_dlen = cpu_to_le32(todo / 4);
+
+ cet->t_sym_ctl = 0;
+ cet->t_asym_ctl = 0;
+
+ cet->t_dst[0].addr = cpu_to_le32(dma_dst);
+ cet->t_dst[0].len = cpu_to_le32(todo / 4);
+ ce->chanlist[flow].timeout = todo;
+
+ err = sun8i_ce_run_task(ce, 3, "TRNG");
+ mutex_unlock(&ce->rnglock);
+
+ pm_runtime_put(ce->dev);
+
+err_pm:
+ dma_unmap_single(ce->dev, dma_dst, todo, DMA_FROM_DEVICE);
+
+ if (!err) {
+ memcpy(data, d, max);
+ err = max;
+ }
+ memzero_explicit(d, todo);
+err_dst:
+ kfree(d);
+ return err;
+}
+
+int sun8i_ce_hwrng_register(struct sun8i_ce_dev *ce)
+{
+ int ret;
+
+ if (ce->variant->trng == CE_ID_NOTSUPP) {
+ dev_info(ce->dev, "TRNG not supported\n");
+ return 0;
+ }
+ ce->trng.name = "sun8i Crypto Engine TRNG";
+ ce->trng.read = sun8i_ce_trng_read;
+ ce->trng.quality = 1000;
+
+ ret = hwrng_register(&ce->trng);
+ if (ret)
+ dev_err(ce->dev, "Fail to register the TRNG\n");
+ return ret;
+}
+
+void sun8i_ce_hwrng_unregister(struct sun8i_ce_dev *ce)
+{
+ if (ce->variant->trng == CE_ID_NOTSUPP)
+ return;
+ hwrng_unregister(&ce->trng);
+}