cc_driver.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2012-2019 ARM Limited or its affiliates. */

#include <linux/kernel.h>
#include <linux/module.h>

#include <linux/crypto.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/of.h>
#include <linux/clk.h>
#include <linux/of_address.h>
#include <linux/pm_runtime.h>

#include "cc_driver.h"
#include "cc_request_mgr.h"
#include "cc_buffer_mgr.h"
#include "cc_debugfs.h"
#include "cc_cipher.h"
#include "cc_aead.h"
#include "cc_hash.h"
#include "cc_sram_mgr.h"
#include "cc_pm.h"
#include "cc_fips.h"

bool cc_dump_desc;
module_param_named(dump_desc, cc_dump_desc, bool, 0600);
MODULE_PARM_DESC(cc_dump_desc, "Dump descriptors to kernel log as debugging aid");
bool cc_dump_bytes;
module_param_named(dump_bytes, cc_dump_bytes, bool, 0600);
MODULE_PARM_DESC(cc_dump_bytes, "Dump buffers to kernel log as debugging aid");

static bool cc_sec_disable;
module_param_named(sec_disable, cc_sec_disable, bool, 0600);
MODULE_PARM_DESC(cc_sec_disable, "Disable security functions");

struct cc_hw_data {
	char *name;
	enum cc_hw_rev rev;
	u32 sig;
	u32 cidr_0123;
	u32 pidr_0124;
	int std_bodies;
};

#define CC_NUM_IDRS 4
#define CC_HW_RESET_LOOP_COUNT 10

/* Note: PIDR3 holds CMOD/Rev so ignored for HW identification purposes */
static const u32 pidr_0124_offsets[CC_NUM_IDRS] = {
	CC_REG(PERIPHERAL_ID_0), CC_REG(PERIPHERAL_ID_1),
	CC_REG(PERIPHERAL_ID_2), CC_REG(PERIPHERAL_ID_4)
};

static const u32 cidr_0123_offsets[CC_NUM_IDRS] = {
	CC_REG(COMPONENT_ID_0), CC_REG(COMPONENT_ID_1),
	CC_REG(COMPONENT_ID_2), CC_REG(COMPONENT_ID_3)
};

/* Hardware revisions defs. */

/* The 703 is a OSCCA only variant of the 713 */
static const struct cc_hw_data cc703_hw = {
	.name = "703", .rev = CC_HW_REV_713, .cidr_0123 = 0xB105F00DU,
	.pidr_0124 = 0x040BB0D0U, .std_bodies = CC_STD_OSCCA
};

static const struct cc_hw_data cc713_hw = {
	.name = "713", .rev = CC_HW_REV_713, .cidr_0123 = 0xB105F00DU,
	.pidr_0124 = 0x040BB0D0U, .std_bodies = CC_STD_ALL
};

static const struct cc_hw_data cc712_hw = {
	.name = "712", .rev = CC_HW_REV_712, .sig =  0xDCC71200U,
	.std_bodies = CC_STD_ALL
};

static const struct cc_hw_data cc710_hw = {
	.name = "710", .rev = CC_HW_REV_710, .sig =  0xDCC63200U,
	.std_bodies = CC_STD_ALL
};

static const struct cc_hw_data cc630p_hw = {
	.name = "630P", .rev = CC_HW_REV_630, .sig = 0xDCC63000U,
	.std_bodies = CC_STD_ALL
};

static const struct of_device_id arm_ccree_dev_of_match[] = {
	{ .compatible = "arm,cryptocell-703-ree", .data = &cc703_hw },
	{ .compatible = "arm,cryptocell-713-ree", .data = &cc713_hw },
	{ .compatible = "arm,cryptocell-712-ree", .data = &cc712_hw },
	{ .compatible = "arm,cryptocell-710-ree", .data = &cc710_hw },
	{ .compatible = "arm,cryptocell-630p-ree", .data = &cc630p_hw },
	{}
};
MODULE_DEVICE_TABLE(of, arm_ccree_dev_of_match);

static void init_cc_cache_params(struct cc_drvdata *drvdata)
{
	struct device *dev = drvdata_to_dev(drvdata);
	u32 cache_params, ace_const, val;
	u64 mask;

	/* compute CC_AXIM_CACHE_PARAMS */
	cache_params = cc_ioread(drvdata, CC_REG(AXIM_CACHE_PARAMS));
	dev_dbg(dev, "Cache params previous: 0x%08X\n", cache_params);

	/* non cached or write-back, write allocate */
	val = drvdata->coherent ? 0xb : 0x2;

	mask = CC_GENMASK(CC_AXIM_CACHE_PARAMS_AWCACHE);
	cache_params &= ~mask;
	cache_params |= FIELD_PREP(mask, val);

	mask = CC_GENMASK(CC_AXIM_CACHE_PARAMS_AWCACHE_LAST);
	cache_params &= ~mask;
	cache_params |= FIELD_PREP(mask, val);

	mask = CC_GENMASK(CC_AXIM_CACHE_PARAMS_ARCACHE);
	cache_params &= ~mask;
	cache_params |= FIELD_PREP(mask, val);

	drvdata->cache_params = cache_params;

	dev_dbg(dev, "Cache params current: 0x%08X\n", cache_params);

	if (drvdata->hw_rev <= CC_HW_REV_710)
		return;

	/* compute CC_AXIM_ACE_CONST */
	ace_const = cc_ioread(drvdata, CC_REG(AXIM_ACE_CONST));
	dev_dbg(dev, "ACE-const previous: 0x%08X\n", ace_const);

	/* system or outer-sharable */
	val = drvdata->coherent ? 0x2 : 0x3;

	mask = CC_GENMASK(CC_AXIM_ACE_CONST_ARDOMAIN);
	ace_const &= ~mask;
	ace_const |= FIELD_PREP(mask, val);

	mask = CC_GENMASK(CC_AXIM_ACE_CONST_AWDOMAIN);
	ace_const &= ~mask;
	ace_const |= FIELD_PREP(mask, val);

	dev_dbg(dev, "ACE-const current: 0x%08X\n", ace_const);

	drvdata->ace_const = ace_const;
}

static u32 cc_read_idr(struct cc_drvdata *drvdata, const u32 *idr_offsets)
{
	int i;
	union {
		u8 regs[CC_NUM_IDRS];
		__le32 val;
	} idr;

	for (i = 0; i < CC_NUM_IDRS; ++i)
		idr.regs[i] = cc_ioread(drvdata, idr_offsets[i]);

	return le32_to_cpu(idr.val);
}

void __dump_byte_array(const char *name, const u8 *buf, size_t len)
{
	char prefix[64];

	if (!buf)
		return;

	snprintf(prefix, sizeof(prefix), "%s[%zu]: ", name, len);

	print_hex_dump(KERN_DEBUG, prefix, DUMP_PREFIX_ADDRESS, 16, 1, buf,
		       len, false);
}

static irqreturn_t cc_isr(int irq, void *dev_id)
{
	struct cc_drvdata *drvdata = (struct cc_drvdata *)dev_id;
	struct device *dev = drvdata_to_dev(drvdata);
	u32 irr;
	u32 imr;

	/* STAT_OP_TYPE_GENERIC STAT_PHASE_0: Interrupt */
	/* if driver suspended return, probably shared interrupt */
	if (pm_runtime_suspended(dev))
		return IRQ_NONE;

	/* read the interrupt status */
	irr = cc_ioread(drvdata, CC_REG(HOST_IRR));
	dev_dbg(dev, "Got IRR=0x%08X\n", irr);

	if (irr == 0) /* Probably shared interrupt line */
		return IRQ_NONE;

	imr = cc_ioread(drvdata, CC_REG(HOST_IMR));

	/* clear interrupt - must be before processing events */
	cc_iowrite(drvdata, CC_REG(HOST_ICR), irr);

	drvdata->irq = irr;
	/* Completion interrupt - most probable */
	if (irr & drvdata->comp_mask) {
		/* Mask all completion interrupts - will be unmasked in
		 * deferred service handler
		 */
		cc_iowrite(drvdata, CC_REG(HOST_IMR), imr | drvdata->comp_mask);
		irr &= ~drvdata->comp_mask;
		complete_request(drvdata);
	}
#ifdef CONFIG_CRYPTO_FIPS
	/* TEE FIPS interrupt */
	if (irr & CC_GPR0_IRQ_MASK) {
		/* Mask interrupt - will be unmasked in Deferred service
		 * handler
		 */
		cc_iowrite(drvdata, CC_REG(HOST_IMR), imr | CC_GPR0_IRQ_MASK);
		irr &= ~CC_GPR0_IRQ_MASK;
		fips_handler(drvdata);
	}
#endif
	/* AXI error interrupt */
	if (irr & CC_AXI_ERR_IRQ_MASK) {
		u32 axi_err;

		/* Read the AXI error ID */
		axi_err = cc_ioread(drvdata, CC_REG(AXIM_MON_ERR));
		dev_dbg(dev, "AXI completion error: axim_mon_err=0x%08X\n",
			axi_err);

		irr &= ~CC_AXI_ERR_IRQ_MASK;
	}

	if (irr) {
		dev_dbg_ratelimited(dev, "IRR includes unknown cause bits (0x%08X)\n",
				    irr);
		/* Just warning */
	}

	return IRQ_HANDLED;
}

bool cc_wait_for_reset_completion(struct cc_drvdata *drvdata)
{
	unsigned int val;
	unsigned int i;

	/* 712/710/63 has no reset completion indication, always return true */
	if (drvdata->hw_rev <= CC_HW_REV_712)
		return true;

	for (i = 0; i < CC_HW_RESET_LOOP_COUNT; i++) {
		/* in cc7x3 NVM_IS_IDLE indicates that CC reset is
		 *  completed and device is fully functional
		 */
		val = cc_ioread(drvdata, CC_REG(NVM_IS_IDLE));
		if (val & CC_NVM_IS_IDLE_MASK) {
			/* hw indicate reset completed */
			return true;
		}
		/* allow scheduling other process on the processor */
		schedule();
	}
	/* reset not completed */
	return false;
}

int init_cc_regs(struct cc_drvdata *drvdata)
{
	unsigned int val;
	struct device *dev = drvdata_to_dev(drvdata);

	/* Unmask all AXI interrupt sources AXI_CFG1 register   */
	/* AXI interrupt config are obsoleted startign at cc7x3 */
	if (drvdata->hw_rev <= CC_HW_REV_712) {
		val = cc_ioread(drvdata, CC_REG(AXIM_CFG));
		cc_iowrite(drvdata, CC_REG(AXIM_CFG), val & ~CC_AXI_IRQ_MASK);
		dev_dbg(dev, "AXIM_CFG=0x%08X\n",
			cc_ioread(drvdata, CC_REG(AXIM_CFG)));
	}

	/* Clear all pending interrupts */
	val = cc_ioread(drvdata, CC_REG(HOST_IRR));
	dev_dbg(dev, "IRR=0x%08X\n", val);
	cc_iowrite(drvdata, CC_REG(HOST_ICR), val);

	/* Unmask relevant interrupt cause */
	val = drvdata->comp_mask | CC_AXI_ERR_IRQ_MASK;

	if (drvdata->hw_rev >= CC_HW_REV_712)
		val |= CC_GPR0_IRQ_MASK;

	cc_iowrite(drvdata, CC_REG(HOST_IMR), ~val);

	cc_iowrite(drvdata, CC_REG(AXIM_CACHE_PARAMS), drvdata->cache_params);
	if (drvdata->hw_rev >= CC_HW_REV_712)
		cc_iowrite(drvdata, CC_REG(AXIM_ACE_CONST), drvdata->ace_const);

	return 0;
}

static int init_cc_resources(struct platform_device *plat_dev)
{
	struct resource *req_mem_cc_regs = NULL;
	struct cc_drvdata *new_drvdata;
	struct device *dev = &plat_dev->dev;
	struct device_node *np = dev->of_node;
	u32 val, hw_rev_pidr, sig_cidr;
	u64 dma_mask;
	const struct cc_hw_data *hw_rev;
	struct clk *clk;
	int irq;
	int rc = 0;

	new_drvdata = devm_kzalloc(dev, sizeof(*new_drvdata), GFP_KERNEL);
	if (!new_drvdata)
		return -ENOMEM;

	hw_rev = of_device_get_match_data(dev);
	new_drvdata->hw_rev_name = hw_rev->name;
	new_drvdata->hw_rev = hw_rev->rev;
	new_drvdata->std_bodies = hw_rev->std_bodies;

	if (hw_rev->rev >= CC_HW_REV_712) {
		new_drvdata->axim_mon_offset = CC_REG(AXIM_MON_COMP);
		new_drvdata->sig_offset = CC_REG(HOST_SIGNATURE_712);
		new_drvdata->ver_offset = CC_REG(HOST_VERSION_712);
	} else {
		new_drvdata->axim_mon_offset = CC_REG(AXIM_MON_COMP8);
		new_drvdata->sig_offset = CC_REG(HOST_SIGNATURE_630);
		new_drvdata->ver_offset = CC_REG(HOST_VERSION_630);
	}

	new_drvdata->comp_mask = CC_COMP_IRQ_MASK;

	platform_set_drvdata(plat_dev, new_drvdata);
	new_drvdata->plat_dev = plat_dev;

	clk = devm_clk_get_optional(dev, NULL);
	if (IS_ERR(clk))
		return dev_err_probe(dev, PTR_ERR(clk), "Error getting clock\n");
	new_drvdata->clk = clk;

	new_drvdata->coherent = of_dma_is_coherent(np);

	/* Get device resources */
	/* First CC registers space */
	/* Map registers space */
	new_drvdata->cc_base = devm_platform_get_and_ioremap_resource(plat_dev,
								      0, &req_mem_cc_regs);
	if (IS_ERR(new_drvdata->cc_base))
		return PTR_ERR(new_drvdata->cc_base);

	dev_dbg(dev, "Got MEM resource (%s): %pR\n", req_mem_cc_regs->name,
		req_mem_cc_regs);
	dev_dbg(dev, "CC registers mapped from %pa to 0x%p\n",
		&req_mem_cc_regs->start, new_drvdata->cc_base);

	/* Then IRQ */
	irq = platform_get_irq(plat_dev, 0);
	if (irq < 0)
		return irq;

	init_completion(&new_drvdata->hw_queue_avail);

	if (!dev->dma_mask)
		dev->dma_mask = &dev->coherent_dma_mask;

	dma_mask = DMA_BIT_MASK(DMA_BIT_MASK_LEN);
	rc = dma_set_coherent_mask(dev, dma_mask);
	if (rc) {
		dev_err(dev, "Failed in dma_set_coherent_mask, mask=%llx\n",
			dma_mask);
		return rc;
	}

	rc = clk_prepare_enable(new_drvdata->clk);
	if (rc) {
		dev_err(dev, "Failed to enable clock");
		return rc;
	}

	new_drvdata->sec_disabled = cc_sec_disable;

	pm_runtime_set_autosuspend_delay(dev, CC_SUSPEND_TIMEOUT);
	pm_runtime_use_autosuspend(dev);
	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);
	rc = pm_runtime_get_sync(dev);
	if (rc < 0) {
		dev_err(dev, "pm_runtime_get_sync() failed: %d\n", rc);
		goto post_pm_err;
	}

	/* Wait for Cryptocell reset completion */
	if (!cc_wait_for_reset_completion(new_drvdata)) {
		dev_err(dev, "Cryptocell reset not completed");
	}

	if (hw_rev->rev <= CC_HW_REV_712) {
		/* Verify correct mapping */
		val = cc_ioread(new_drvdata, new_drvdata->sig_offset);
		if (val != hw_rev->sig) {
			dev_err(dev, "Invalid CC signature: SIGNATURE=0x%08X != expected=0x%08X\n",
				val, hw_rev->sig);
			rc = -EINVAL;
			goto post_pm_err;
		}
		sig_cidr = val;
		hw_rev_pidr = cc_ioread(new_drvdata, new_drvdata->ver_offset);
	} else {
		/* Verify correct mapping */
		val = cc_read_idr(new_drvdata, pidr_0124_offsets);
		if (val != hw_rev->pidr_0124) {
			dev_err(dev, "Invalid CC PIDR: PIDR0124=0x%08X != expected=0x%08X\n",
				val,  hw_rev->pidr_0124);
			rc = -EINVAL;
			goto post_pm_err;
		}
		hw_rev_pidr = val;

		val = cc_read_idr(new_drvdata, cidr_0123_offsets);
		if (val != hw_rev->cidr_0123) {
			dev_err(dev, "Invalid CC CIDR: CIDR0123=0x%08X != expected=0x%08X\n",
			val,  hw_rev->cidr_0123);
			rc = -EINVAL;
			goto post_pm_err;
		}
		sig_cidr = val;

		/* Check HW engine configuration */
		val = cc_ioread(new_drvdata, CC_REG(HOST_REMOVE_INPUT_PINS));
		switch (val) {
		case CC_PINS_FULL:
			/* This is fine */
			break;
		case CC_PINS_SLIM:
			if (new_drvdata->std_bodies & CC_STD_NIST) {
				dev_warn(dev, "703 mode forced due to HW configuration.\n");
				new_drvdata->std_bodies = CC_STD_OSCCA;
			}
			break;
		default:
			dev_err(dev, "Unsupported engines configuration.\n");
			rc = -EINVAL;
			goto post_pm_err;
		}

		/* Check security disable state */
		val = cc_ioread(new_drvdata, CC_REG(SECURITY_DISABLED));
		val &= CC_SECURITY_DISABLED_MASK;
		new_drvdata->sec_disabled |= !!val;

		if (!new_drvdata->sec_disabled) {
			new_drvdata->comp_mask |= CC_CPP_SM4_ABORT_MASK;
			if (new_drvdata->std_bodies & CC_STD_NIST)
				new_drvdata->comp_mask |= CC_CPP_AES_ABORT_MASK;
		}
	}

	if (new_drvdata->sec_disabled)
		dev_info(dev, "Security Disabled mode is in effect. Security functions disabled.\n");

	/* Display HW versions */
	dev_info(dev, "ARM CryptoCell %s Driver: HW version 0x%08X/0x%8X, Driver version %s\n",
		 hw_rev->name, hw_rev_pidr, sig_cidr, DRV_MODULE_VERSION);
	/* register the driver isr function */
	rc = devm_request_irq(dev, irq, cc_isr, IRQF_SHARED, "ccree",
			      new_drvdata);
	if (rc) {
		dev_err(dev, "Could not register to interrupt %d\n", irq);
		goto post_pm_err;
	}
	dev_dbg(dev, "Registered to IRQ: %d\n", irq);

	init_cc_cache_params(new_drvdata);

	rc = init_cc_regs(new_drvdata);
	if (rc) {
		dev_err(dev, "init_cc_regs failed\n");
		goto post_pm_err;
	}

	rc = cc_debugfs_init(new_drvdata);
	if (rc) {
		dev_err(dev, "Failed registering debugfs interface\n");
		goto post_regs_err;
	}

	rc = cc_fips_init(new_drvdata);
	if (rc) {
		dev_err(dev, "cc_fips_init failed 0x%x\n", rc);
		goto post_debugfs_err;
	}
	rc = cc_sram_mgr_init(new_drvdata);
	if (rc) {
		dev_err(dev, "cc_sram_mgr_init failed\n");
		goto post_fips_init_err;
	}

	new_drvdata->mlli_sram_addr =
		cc_sram_alloc(new_drvdata, MAX_MLLI_BUFF_SIZE);
	if (new_drvdata->mlli_sram_addr == NULL_SRAM_ADDR) {
		rc = -ENOMEM;
		goto post_fips_init_err;
	}

	rc = cc_req_mgr_init(new_drvdata);
	if (rc) {
		dev_err(dev, "cc_req_mgr_init failed\n");
		goto post_fips_init_err;
	}

	rc = cc_buffer_mgr_init(new_drvdata);
	if (rc) {
		dev_err(dev, "cc_buffer_mgr_init failed\n");
		goto post_req_mgr_err;
	}

	/* hash must be allocated first due to use of send_request_init()
	 * and dependency of AEAD on it
	 */
	rc = cc_hash_alloc(new_drvdata);
	if (rc) {
		dev_err(dev, "cc_hash_alloc failed\n");
		goto post_buf_mgr_err;
	}

	/* Allocate crypto algs */
	rc = cc_cipher_alloc(new_drvdata);
	if (rc) {
		dev_err(dev, "cc_cipher_alloc failed\n");
		goto post_hash_err;
	}

	rc = cc_aead_alloc(new_drvdata);
	if (rc) {
		dev_err(dev, "cc_aead_alloc failed\n");
		goto post_cipher_err;
	}

	/* If we got here and FIPS mode is enabled
	 * it means all FIPS test passed, so let TEE
	 * know we're good.
	 */
	cc_set_ree_fips_status(new_drvdata, true);

	pm_runtime_put(dev);
	return 0;

post_cipher_err:
	cc_cipher_free(new_drvdata);
post_hash_err:
	cc_hash_free(new_drvdata);
post_buf_mgr_err:
	 cc_buffer_mgr_fini(new_drvdata);
post_req_mgr_err:
	cc_req_mgr_fini(new_drvdata);
post_fips_init_err:
	cc_fips_fini(new_drvdata);
post_debugfs_err:
	cc_debugfs_fini(new_drvdata);
post_regs_err:
	fini_cc_regs(new_drvdata);
post_pm_err:
	pm_runtime_put_noidle(dev);
	pm_runtime_disable(dev);
	pm_runtime_set_suspended(dev);
	clk_disable_unprepare(new_drvdata->clk);
	return rc;
}

void fini_cc_regs(struct cc_drvdata *drvdata)
{
	/* Mask all interrupts */
	cc_iowrite(drvdata, CC_REG(HOST_IMR), 0xFFFFFFFF);
}

static void cleanup_cc_resources(struct platform_device *plat_dev)
{
	struct device *dev = &plat_dev->dev;
	struct cc_drvdata *drvdata =
		(struct cc_drvdata *)platform_get_drvdata(plat_dev);

	cc_aead_free(drvdata);
	cc_cipher_free(drvdata);
	cc_hash_free(drvdata);
	cc_buffer_mgr_fini(drvdata);
	cc_req_mgr_fini(drvdata);
	cc_fips_fini(drvdata);
	cc_debugfs_fini(drvdata);
	fini_cc_regs(drvdata);
	pm_runtime_put_noidle(dev);
	pm_runtime_disable(dev);
	pm_runtime_set_suspended(dev);
	clk_disable_unprepare(drvdata->clk);
}

unsigned int cc_get_default_hash_len(struct cc_drvdata *drvdata)
{
	if (drvdata->hw_rev >= CC_HW_REV_712)
		return HASH_LEN_SIZE_712;
	else
		return HASH_LEN_SIZE_630;
}

static int ccree_probe(struct platform_device *plat_dev)
{
	int rc;
	struct device *dev = &plat_dev->dev;

	/* Map registers space */
	rc = init_cc_resources(plat_dev);
	if (rc)
		return rc;

	dev_info(dev, "ARM ccree device initialized\n");

	return 0;
}

static void ccree_remove(struct platform_device *plat_dev)
{
	struct device *dev = &plat_dev->dev;

	dev_dbg(dev, "Releasing ccree resources...\n");

	cleanup_cc_resources(plat_dev);

	dev_info(dev, "ARM ccree device terminated\n");
}

static struct platform_driver ccree_driver = {
	.driver = {
		   .name = "ccree",
		   .of_match_table = arm_ccree_dev_of_match,
#ifdef CONFIG_PM
		   .pm = &ccree_pm,
#endif
	},
	.probe = ccree_probe,
	.remove = ccree_remove,
};

static int __init ccree_init(void)
{
	int rc;

	cc_debugfs_global_init();

	rc = platform_driver_register(&ccree_driver);
	if (rc) {
		cc_debugfs_global_fini();
		return rc;
	}

	return 0;
}
module_init(ccree_init);

static void __exit ccree_exit(void)
{
	platform_driver_unregister(&ccree_driver);
	cc_debugfs_global_fini();
}
module_exit(ccree_exit);

/* Module description */
MODULE_DESCRIPTION("ARM TrustZone CryptoCell REE Driver");
MODULE_VERSION(DRV_MODULE_VERSION);
MODULE_AUTHOR("ARM");
MODULE_LICENSE("GPL v2");