crypto: sl3516 - Add sl3516 crypto engine

The cortina/gemini SL3516 SoC has a crypto IP name either (crypto
engine/crypto acceleration engine in the datasheet).
It support many algorithms like [AES|DES|3DES][ECB|CBC], SHA1, MD5 and
some HMAC.

This patch adds the core files and support for ecb(aes) and the RNG.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 535 insertions, 0 deletions

diff --git a/drivers/crypto/gemini/sl3516-ce-core.c b/drivers/crypto/gemini/sl3516-ce-core.c
new file mode 100644
index 000000000000..da6cd529a6c0
--- /dev/null
+++ b/drivers/crypto/gemini/sl3516-ce-core.c
@@ -0,0 +1,535 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * sl3516-ce-core.c - hardware cryptographic offloader for Stormlink SL3516 SoC
+ *
+ * Copyright (C) 2021 Corentin Labbe <clabbe@baylibre.com>
+ *
+ * Core file which registers crypto algorithms supported by the CryptoEngine
+ */
+#include <linux/clk.h>
+#include <linux/crypto.h>
+#include <linux/debugfs.h>
+#include <linux/dev_printk.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+#include <crypto/internal/rng.h>
+#include <crypto/internal/skcipher.h>
+
+#include "sl3516-ce.h"
+
+static int sl3516_ce_desc_init(struct sl3516_ce_dev *ce)
+{
+	const size_t sz = sizeof(struct descriptor) * MAXDESC;
+	int i;
+
+	ce->tx = dma_alloc_coherent(ce->dev, sz, &ce->dtx, GFP_KERNEL);
+	if (!ce->tx)
+		return -ENOMEM;
+	ce->rx = dma_alloc_coherent(ce->dev, sz, &ce->drx, GFP_KERNEL);
+	if (!ce->rx)
+		goto err_rx;
+
+	for (i = 0; i < MAXDESC; i++) {
+		ce->tx[i].frame_ctrl.bits.own = CE_CPU;
+		ce->tx[i].next_desc.next_descriptor = ce->dtx + (i + 1) * sizeof(struct descriptor);
+	}
+	ce->tx[MAXDESC - 1].next_desc.next_descriptor = ce->dtx;
+
+	for (i = 0; i < MAXDESC; i++) {
+		ce->rx[i].frame_ctrl.bits.own = CE_CPU;
+		ce->rx[i].next_desc.next_descriptor = ce->drx + (i + 1) * sizeof(struct descriptor);
+	}
+	ce->rx[MAXDESC - 1].next_desc.next_descriptor = ce->drx;
+
+	ce->pctrl = dma_alloc_coherent(ce->dev, sizeof(struct pkt_control_ecb),
+				       &ce->dctrl, GFP_KERNEL);
+	if (!ce->pctrl)
+		goto err_pctrl;
+
+	return 0;
+err_pctrl:
+	dma_free_coherent(ce->dev, sz, ce->rx, ce->drx);
+err_rx:
+	dma_free_coherent(ce->dev, sz, ce->tx, ce->dtx);
+	return -ENOMEM;
+}
+
+static void sl3516_ce_free_descs(struct sl3516_ce_dev *ce)
+{
+	const size_t sz = sizeof(struct descriptor) * MAXDESC;
+
+	dma_free_coherent(ce->dev, sz, ce->tx, ce->dtx);
+	dma_free_coherent(ce->dev, sz, ce->rx, ce->drx);
+	dma_free_coherent(ce->dev, sizeof(struct pkt_control_ecb), ce->pctrl,
+			  ce->dctrl);
+}
+
+static void start_dma_tx(struct sl3516_ce_dev *ce)
+{
+	u32 v;
+
+	v = TXDMA_CTRL_START | TXDMA_CTRL_CHAIN_MODE | TXDMA_CTRL_CONTINUE | \
+		TXDMA_CTRL_INT_FAIL | TXDMA_CTRL_INT_PERR | TXDMA_CTRL_BURST_UNK;
+
+	writel(v, ce->base + IPSEC_TXDMA_CTRL);
+}
+
+static void start_dma_rx(struct sl3516_ce_dev *ce)
+{
+	u32 v;
+
+	v = RXDMA_CTRL_START | RXDMA_CTRL_CHAIN_MODE | RXDMA_CTRL_CONTINUE | \
+		RXDMA_CTRL_BURST_UNK | RXDMA_CTRL_INT_FINISH | \
+		RXDMA_CTRL_INT_FAIL | RXDMA_CTRL_INT_PERR | \
+		RXDMA_CTRL_INT_EOD | RXDMA_CTRL_INT_EOF;
+
+	writel(v, ce->base + IPSEC_RXDMA_CTRL);
+}
+
+static struct descriptor *get_desc_tx(struct sl3516_ce_dev *ce)
+{
+	struct descriptor *dd;
+
+	dd = &ce->tx[ce->ctx];
+	ce->ctx++;
+	if (ce->ctx >= MAXDESC)
+		ce->ctx = 0;
+	return dd;
+}
+
+static struct descriptor *get_desc_rx(struct sl3516_ce_dev *ce)
+{
+	struct descriptor *rdd;
+
+	rdd = &ce->rx[ce->crx];
+	ce->crx++;
+	if (ce->crx >= MAXDESC)
+		ce->crx = 0;
+	return rdd;
+}
+
+int sl3516_ce_run_task(struct sl3516_ce_dev *ce, struct sl3516_ce_cipher_req_ctx *rctx,
+		       const char *name)
+{
+	struct descriptor *dd, *rdd = NULL;
+	u32 v;
+	int i, err = 0;
+
+	ce->stat_req++;
+
+	reinit_completion(&ce->complete);
+	ce->status = 0;
+
+	for (i = 0; i < rctx->nr_sgd; i++) {
+		dev_dbg(ce->dev, "%s handle DST SG %d/%d len=%d\n", __func__,
+			i, rctx->nr_sgd, rctx->t_dst[i].len);
+		rdd = get_desc_rx(ce);
+		rdd->buf_adr = rctx->t_dst[i].addr;
+		rdd->frame_ctrl.bits.buffer_size = rctx->t_dst[i].len;
+		rdd->frame_ctrl.bits.own = CE_DMA;
+	}
+	rdd->next_desc.bits.eofie = 1;
+
+	for (i = 0; i < rctx->nr_sgs; i++) {
+		dev_dbg(ce->dev, "%s handle SRC SG %d/%d len=%d\n", __func__,
+			i, rctx->nr_sgs, rctx->t_src[i].len);
+		rctx->h->algorithm_len = rctx->t_src[i].len;
+
+		dd = get_desc_tx(ce);
+		dd->frame_ctrl.raw = 0;
+		dd->flag_status.raw = 0;
+		dd->frame_ctrl.bits.buffer_size = rctx->pctrllen;
+		dd->buf_adr = ce->dctrl;
+		dd->flag_status.tx_flag.tqflag = rctx->tqflag;
+		dd->next_desc.bits.eofie = 0;
+		dd->next_desc.bits.dec = 0;
+		dd->next_desc.bits.sof_eof = DESC_FIRST | DESC_LAST;
+		dd->frame_ctrl.bits.own = CE_DMA;
+
+		dd = get_desc_tx(ce);
+		dd->frame_ctrl.raw = 0;
+		dd->flag_status.raw = 0;
+		dd->frame_ctrl.bits.buffer_size = rctx->t_src[i].len;
+		dd->buf_adr = rctx->t_src[i].addr;
+		dd->flag_status.tx_flag.tqflag = 0;
+		dd->next_desc.bits.eofie = 0;
+		dd->next_desc.bits.dec = 0;
+		dd->next_desc.bits.sof_eof = DESC_FIRST | DESC_LAST;
+		dd->frame_ctrl.bits.own = CE_DMA;
+		start_dma_tx(ce);
+		start_dma_rx(ce);
+	}
+	wait_for_completion_interruptible_timeout(&ce->complete,
+						  msecs_to_jiffies(5000));
+	if (ce->status == 0) {
+		dev_err(ce->dev, "DMA timeout for %s\n", name);
+		err = -EFAULT;
+	}
+	v = readl(ce->base + IPSEC_STATUS_REG);
+	if (v & 0xFFF) {
+		dev_err(ce->dev, "IPSEC_STATUS_REG %x\n", v);
+		err = -EFAULT;
+	}
+
+	return err;
+}
+
+static irqreturn_t ce_irq_handler(int irq, void *data)
+{
+	struct sl3516_ce_dev *ce = (struct sl3516_ce_dev *)data;
+	u32 v;
+
+	ce->stat_irq++;
+
+	v = readl(ce->base + IPSEC_DMA_STATUS);
+	writel(v, ce->base + IPSEC_DMA_STATUS);
+
+	if (v & DMA_STATUS_TS_DERR)
+		dev_err(ce->dev, "AHB bus Error While Tx !!!\n");
+	if (v & DMA_STATUS_TS_PERR)
+		dev_err(ce->dev, "Tx Descriptor Protocol Error !!!\n");
+	if (v & DMA_STATUS_RS_DERR)
+		dev_err(ce->dev, "AHB bus Error While Rx !!!\n");
+	if (v & DMA_STATUS_RS_PERR)
+		dev_err(ce->dev, "Rx Descriptor Protocol Error !!!\n");
+
+	if (v & DMA_STATUS_TS_EOFI)
+		ce->stat_irq_tx++;
+	if (v & DMA_STATUS_RS_EOFI) {
+		ce->status = 1;
+		complete(&ce->complete);
+		ce->stat_irq_rx++;
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_HANDLED;
+}
+
+static struct sl3516_ce_alg_template ce_algs[] = {
+{
+	.type = CRYPTO_ALG_TYPE_SKCIPHER,
+	.mode = ECB_AES,
+	.alg.skcipher = {
+		.base = {
+			.cra_name = "ecb(aes)",
+			.cra_driver_name = "ecb-aes-sl3516",
+			.cra_priority = 400,
+			.cra_blocksize = AES_BLOCK_SIZE,
+			.cra_flags = CRYPTO_ALG_TYPE_SKCIPHER |
+				CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
+			.cra_ctxsize = sizeof(struct sl3516_ce_cipher_tfm_ctx),
+			.cra_module = THIS_MODULE,
+			.cra_alignmask = 0xf,
+			.cra_init = sl3516_ce_cipher_init,
+			.cra_exit = sl3516_ce_cipher_exit,
+		},
+		.min_keysize	= AES_MIN_KEY_SIZE,
+		.max_keysize	= AES_MAX_KEY_SIZE,
+		.setkey		= sl3516_ce_aes_setkey,
+		.encrypt	= sl3516_ce_skencrypt,
+		.decrypt	= sl3516_ce_skdecrypt,
+	}
+},
+};
+
+#ifdef CONFIG_CRYPTO_DEV_SL3516_DEBUG
+static int sl3516_ce_debugfs_show(struct seq_file *seq, void *v)
+{
+	struct sl3516_ce_dev *ce = seq->private;
+	unsigned int i;
+
+	seq_printf(seq, "HWRNG %lu %lu\n",
+		   ce->hwrng_stat_req, ce->hwrng_stat_bytes);
+	seq_printf(seq, "IRQ %lu\n", ce->stat_irq);
+	seq_printf(seq, "IRQ TX %lu\n", ce->stat_irq_tx);
+	seq_printf(seq, "IRQ RX %lu\n", ce->stat_irq_rx);
+	seq_printf(seq, "nreq %lu\n", ce->stat_req);
+	seq_printf(seq, "fallback SG count TX %lu\n", ce->fallback_sg_count_tx);
+	seq_printf(seq, "fallback SG count RX %lu\n", ce->fallback_sg_count_rx);
+	seq_printf(seq, "fallback modulo16 %lu\n", ce->fallback_mod16);
+	seq_printf(seq, "fallback align16 %lu\n", ce->fallback_align16);
+	seq_printf(seq, "fallback not same len %lu\n", ce->fallback_not_same_len);
+
+	for (i = 0; i < ARRAY_SIZE(ce_algs); i++) {
+		if (!ce_algs[i].ce)
+			continue;
+		switch (ce_algs[i].type) {
+		case CRYPTO_ALG_TYPE_SKCIPHER:
+			seq_printf(seq, "%s %s reqs=%lu fallback=%lu\n",
+				   ce_algs[i].alg.skcipher.base.cra_driver_name,
+				   ce_algs[i].alg.skcipher.base.cra_name,
+				   ce_algs[i].stat_req, ce_algs[i].stat_fb);
+			break;
+		}
+	}
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(sl3516_ce_debugfs);
+#endif
+
+static int sl3516_ce_register_algs(struct sl3516_ce_dev *ce)
+{
+	int err;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(ce_algs); i++) {
+		ce_algs[i].ce = ce;
+		switch (ce_algs[i].type) {
+		case CRYPTO_ALG_TYPE_SKCIPHER:
+			dev_info(ce->dev, "DEBUG: Register %s\n",
+				 ce_algs[i].alg.skcipher.base.cra_name);
+			err = crypto_register_skcipher(&ce_algs[i].alg.skcipher);
+			if (err) {
+				dev_err(ce->dev, "Fail to register %s\n",
+					ce_algs[i].alg.skcipher.base.cra_name);
+				ce_algs[i].ce = NULL;
+				return err;
+			}
+			break;
+		default:
+			ce_algs[i].ce = NULL;
+			dev_err(ce->dev, "ERROR: tried to register an unknown algo\n");
+		}
+	}
+	return 0;
+}
+
+static void sl3516_ce_unregister_algs(struct sl3516_ce_dev *ce)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(ce_algs); i++) {
+		if (!ce_algs[i].ce)
+			continue;
+		switch (ce_algs[i].type) {
+		case CRYPTO_ALG_TYPE_SKCIPHER:
+			dev_info(ce->dev, "Unregister %d %s\n", i,
+				 ce_algs[i].alg.skcipher.base.cra_name);
+			crypto_unregister_skcipher(&ce_algs[i].alg.skcipher);
+			break;
+		}
+	}
+}
+
+static void sl3516_ce_start(struct sl3516_ce_dev *ce)
+{
+	ce->ctx = 0;
+	ce->crx = 0;
+	writel(ce->dtx, ce->base + IPSEC_TXDMA_CURR_DESC);
+	writel(ce->drx, ce->base + IPSEC_RXDMA_CURR_DESC);
+	writel(0, ce->base + IPSEC_DMA_STATUS);
+}
+
+/*
+ * Power management strategy: The device is suspended unless a TFM exists for
+ * one of the algorithms proposed by this driver.
+ */
+static int sl3516_ce_pm_suspend(struct device *dev)
+{
+	struct sl3516_ce_dev *ce = dev_get_drvdata(dev);
+
+	reset_control_assert(ce->reset);
+	clk_disable_unprepare(ce->clks);
+	return 0;
+}
+
+static int sl3516_ce_pm_resume(struct device *dev)
+{
+	struct sl3516_ce_dev *ce = dev_get_drvdata(dev);
+	int err;
+
+	err = clk_prepare_enable(ce->clks);
+	if (err) {
+		dev_err(ce->dev, "Cannot prepare_enable\n");
+		goto error;
+	}
+	err = reset_control_deassert(ce->reset);
+	if (err) {
+		dev_err(ce->dev, "Cannot deassert reset control\n");
+		goto error;
+	}
+
+	sl3516_ce_start(ce);
+
+	return 0;
+error:
+	sl3516_ce_pm_suspend(dev);
+	return err;
+}
+
+static const struct dev_pm_ops sl3516_ce_pm_ops = {
+	SET_RUNTIME_PM_OPS(sl3516_ce_pm_suspend, sl3516_ce_pm_resume, NULL)
+};
+
+static int sl3516_ce_pm_init(struct sl3516_ce_dev *ce)
+{
+	int err;
+
+	pm_runtime_use_autosuspend(ce->dev);
+	pm_runtime_set_autosuspend_delay(ce->dev, 2000);
+
+	err = pm_runtime_set_suspended(ce->dev);
+	if (err)
+		return err;
+	pm_runtime_enable(ce->dev);
+	return err;
+}
+
+static void sl3516_ce_pm_exit(struct sl3516_ce_dev *ce)
+{
+	pm_runtime_disable(ce->dev);
+}
+
+static int sl3516_ce_probe(struct platform_device *pdev)
+{
+	struct sl3516_ce_dev *ce;
+	int err, irq;
+	u32 v;
+
+	ce = devm_kzalloc(&pdev->dev, sizeof(*ce), GFP_KERNEL);
+	if (!ce)
+		return -ENOMEM;
+
+	ce->dev = &pdev->dev;
+	platform_set_drvdata(pdev, ce);
+
+	ce->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ce->base))
+		return PTR_ERR(ce->base);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	err = devm_request_irq(&pdev->dev, irq, ce_irq_handler, 0, "crypto", ce);
+	if (err) {
+		dev_err(ce->dev, "Cannot request Crypto Engine IRQ (err=%d)\n", err);
+		return err;
+	}
+
+	ce->reset = devm_reset_control_get(&pdev->dev, NULL);
+	if (IS_ERR(ce->reset))
+		return dev_err_probe(&pdev->dev, PTR_ERR(ce->reset),
+				     "No reset control found\n");
+	ce->clks = devm_clk_get(ce->dev, NULL);
+	if (IS_ERR(ce->clks)) {
+		err = PTR_ERR(ce->clks);
+		dev_err(ce->dev, "Cannot get clock err=%d\n", err);
+		return err;
+	}
+
+	err = sl3516_ce_desc_init(ce);
+	if (err)
+		return err;
+
+	err = sl3516_ce_pm_init(ce);
+	if (err)
+		goto error_pm;
+
+	init_completion(&ce->complete);
+
+	ce->engine = crypto_engine_alloc_init(ce->dev, true);
+	if (!ce->engine) {
+		dev_err(ce->dev, "Cannot allocate engine\n");
+		err = -ENOMEM;
+		goto error_engine;
+	}
+
+	err = crypto_engine_start(ce->engine);
+	if (err) {
+		dev_err(ce->dev, "Cannot start engine\n");
+		goto error_engine;
+	}
+
+	err = sl3516_ce_register_algs(ce);
+	if (err)
+		goto error_alg;
+
+	err = sl3516_ce_rng_register(ce);
+	if (err)
+		goto error_rng;
+
+	err = pm_runtime_resume_and_get(ce->dev);
+	if (err < 0)
+		goto error_pmuse;
+
+	v = readl(ce->base + IPSEC_ID);
+	dev_info(ce->dev, "SL3516 dev %lx rev %lx\n",
+		 v & GENMASK(31, 4),
+		 v & GENMASK(3, 0));
+	v = readl(ce->base + IPSEC_DMA_DEVICE_ID);
+	dev_info(ce->dev, "SL3516 DMA dev %lx rev %lx\n",
+		 v & GENMASK(15, 4),
+		 v & GENMASK(3, 0));
+
+	pm_runtime_put_sync(ce->dev);
+
+#ifdef CONFIG_CRYPTO_DEV_SL3516_DEBUG
+	/* Ignore error of debugfs */
+	ce->dbgfs_dir = debugfs_create_dir("sl3516", NULL);
+	ce->dbgfs_stats = debugfs_create_file("stats", 0444,
+					      ce->dbgfs_dir, ce,
+					      &sl3516_ce_debugfs_fops);
+#endif
+
+	return 0;
+error_pmuse:
+	sl3516_ce_rng_unregister(ce);
+error_rng:
+	sl3516_ce_unregister_algs(ce);
+error_alg:
+	crypto_engine_exit(ce->engine);
+error_engine:
+	sl3516_ce_pm_exit(ce);
+error_pm:
+	sl3516_ce_free_descs(ce);
+	return err;
+}
+
+static int sl3516_ce_remove(struct platform_device *pdev)
+{
+	struct sl3516_ce_dev *ce = platform_get_drvdata(pdev);
+
+	sl3516_ce_rng_unregister(ce);
+	sl3516_ce_unregister_algs(ce);
+	crypto_engine_exit(ce->engine);
+	sl3516_ce_pm_exit(ce);
+	sl3516_ce_free_descs(ce);
+
+#ifdef CONFIG_CRYPTO_DEV_SL3516_DEBUG
+	debugfs_remove_recursive(ce->dbgfs_dir);
+#endif
+
+	return 0;
+}
+
+static const struct of_device_id sl3516_ce_crypto_of_match_table[] = {
+	{ .compatible = "cortina,sl3516-crypto"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, sl3516_ce_crypto_of_match_table);
+
+static struct platform_driver sl3516_ce_driver = {
+	.probe		 = sl3516_ce_probe,
+	.remove		 = sl3516_ce_remove,
+	.driver		 = {
+		.name		= "sl3516-crypto",
+		.pm		= &sl3516_ce_pm_ops,
+		.of_match_table	= sl3516_ce_crypto_of_match_table,
+	},
+};
+
+module_platform_driver(sl3516_ce_driver);
+
+MODULE_DESCRIPTION("SL3516 cryptographic offloader");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Corentin Labbe <clabbe@baylibre.com>");