[PATCH 4/6] crypto: add i.MX6 CAAM support

[Steffen Trumtrar]

Hi!

On Mon, Oct 19, 2015 at 08:21:58AM +0200, Sascha Hauer wrote:
> On Wed, Oct 14, 2015 at 03:39:37PM +0200, Steffen Trumtrar wrote:
> > Add the i.MX6 crypto core CAAM.
> > 
> > The core itself works with jobrings in which descriptors can be
> > queued/dequeued for processing.
> 
> Which upstream kernel version is this built upon? What changes did you
> make to the kernel code?
> 
> The answers should be part of the commit message.
> 
> > +static void caam_remove(struct device_d *dev)
> > +{
> > +	struct caam_drv_private *ctrlpriv = dev->priv;
> > +	struct caam_ctrl __iomem *ctrl;
> > +
> > +	ctrl = (struct caam_ctrl __iomem *)ctrlpriv->ctrl;
> 
> This variable is unused.
> 
> > +
> > +	/* De-initialize RNG state handles initialized by this driver. */
> > +	if (ctrlpriv->rng4_sh_init)
> > +		deinstantiate_rng(dev, ctrlpriv->rng4_sh_init);
> > +
> > +	/* shut clocks off before finalizing shutdown */
> > +	clk_disable(ctrlpriv->caam_ipg);
> > +	clk_disable(ctrlpriv->caam_mem);
> > +	clk_disable(ctrlpriv->caam_aclk);
> > +	clk_disable(ctrlpriv->caam_emi_slow);
> > +}
> > +
> > +
> > +	/*
> > +	 * ERRATA:  mx6 devices have an issue wherein AXI bus transactions
> > +	 * may not occur in the correct order. This isn't a problem running
> > +	 * single descriptors, but can be if running multiple concurrent
> > +	 * descriptors. Reworking the driver to throttle to single requests
> > +	 * is impractical, thus the workaround is to limit the AXI pipeline
> > +	 * to a depth of 1 (from it's default of 4) to preclude this situation
> > +	 * from occurring.
> > +	 */
> > +	wr_reg32(&ctrl->mcr,
> > +		 (rd_reg32(&ctrl->mcr) & ~(MCFGR_AXIPIPE_MASK)) |
> > +		 ((1 << MCFGR_AXIPIPE_SHIFT) & MCFGR_AXIPIPE_MASK));
> > +
> > +	wr_reg32(&ctrl->mcr, 0x40002110);
> 
> Hm, first modify some bits and then overwrite the register with some
> hardcoded value?
> 

Oops. I didn't catch that. This is, of course, not correct.

> > +
> > +	/*
> > +	 * Detect and enable JobRs
> > +	 * First, find out how many ring spec'ed, allocate references
> > +	 * for all, then go probe each one.
> > +	 */
> > +	rspec = 0;
> > +	for_each_available_child_of_node(nprop, np)
> > +		if (of_device_is_compatible(np, "fsl,sec-v4.0-job-ring") ||
> > +		    of_device_is_compatible(np, "fsl,sec4.0-job-ring"))
> > +			rspec++;
> > +
> > +	ctrlpriv->jrpdev = xzalloc(sizeof(struct device_d *) * rspec);
> > +	if (ctrlpriv->jrpdev == NULL)
> > +		return -ENOMEM;
> 
> xzalloc does not fail. Several more of these in the code.

Right.

> > +
> > +	ring = 0;
> > +	ctrlpriv->total_jobrs = 0;
> > +	for_each_available_child_of_node(nprop, np)
> > +		if (of_device_is_compatible(np, "fsl,sec-v4.0-job-ring") ||
> > +		    of_device_is_compatible(np, "fsl,sec4.0-job-ring")) {
> > +			struct device_d *jrdev;
> > +
> > +			jrdev = xzalloc(sizeof(*jrdev));
> > +
> > +			strcpy(jrdev->name, np->name);
> > +			jrdev->parent = dev;
> > +			jrdev->device_node = np;
> > +			jrdev->id = DEVICE_ID_SINGLE;
> > +
> > +			ret = register_device(jrdev);
> > +
> > +			if (ret) {
> > +				pr_warn("JR%d Platform device creation error\n",
> > +					ring);
> 
> dev_warn
> 
> > diff --git a/drivers/crypto/caam/intern.h b/drivers/crypto/caam/intern.h
> > new file mode 100644
> > index 000000000000..326bda532b83
> > --- /dev/null
> > +++ b/drivers/crypto/caam/intern.h
> > @@ -0,0 +1,105 @@
> > +/*
> > + * CAAM/SEC 4.x driver backend
> > + * Private/internal definitions between modules
> > + *
> > + * Copyright 2008-2011 Freescale Semiconductor, Inc.
> > + *
> > + */
> > +
> > +#ifndef INTERN_H
> > +#define INTERN_H
> > +
> > +struct device;
> 
> Is this needed?
> 
> > +
> > +/* Currently comes from Kconfig param as a ^2 (driver-required) */
> > +#define JOBR_DEPTH (1 << CONFIG_CRYPTO_DEV_FSL_CAAM_RINGSIZE)
> > +
> > +#define JOBR_INTC 0
> > +#define JOBR_INTC_TIME_THLD 0
> > +#define JOBR_INTC_COUNT_THLD 0
> > +
> > +#define pr_hex_dump_debug(prefix_str, prefix_type, rowsize, groupsize, buf, len, ascii) \
> > +	({ \
> > +		(7) <= LOGLEVEL ? print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, groupsize, buf, len, ascii) : 0; \
> > +	})
> 
> 
> This is unused.

> > diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c
> > new file mode 100644
> > index 000000000000..3a82d0559898
> > --- /dev/null
> > +++ b/drivers/crypto/caam/jr.c
> > @@ -0,0 +1,363 @@
> > +/*
> > +* CAAM/SEC 4.x transport/backend driver
> > +* JobR backend functionality
> > + *
> > + * Copyright 2008-2015 Freescale Semiconductor, Inc.
> > + */
> > +
> > +#include <common.h>
> > +#include <clock.h>
> > +#include <dma.h>
> > +#include <driver.h>
> > +#include <init.h>
> > +#include <linux/barebox-wrapper.h>
> > +#include <linux/circ_buf.h>
> > +#include <linux/compiler.h>
> > +#include <linux/err.h>
> > +
> > +#include "regs.h"
> > +#include "jr.h"
> > +#include "desc.h"
> > +#include "desc_constr.h"
> > +#include "error.h"
> > +#include "intern.h"
> > +
> > +static int caam_reset_hw_jr(struct device_d *dev)
> > +{
> > +	struct caam_drv_private_jr *jrp = dev->priv;
> > +	unsigned int timeout = 10000000;
> > +	unsigned int val;
> > +
> > +	/* initiate flush (required prior to reset) */
> > +	wr_reg32(&jrp->rregs->jrcommand, JRCR_RESET);
> > +	do {
> > +		val = rd_reg32(&jrp->rregs->jrintstatus);
> > +		if ((val & JRINT_ERR_HALT_MASK) != JRINT_ERR_HALT_INPROGRESS)
> > +			break;
> > +	} while (--timeout);
> 
> is_timeout() loop please. Several more loops of this kind throughout the
> code.
>
> > +	dev->priv = jrpriv;
> > +	jrpriv->dev = dev;
> > +
> > +	/* save ring identity relative to detection */
> > +	jrpriv->ridx = total_jobrs++;
> > +
> > +	nprop = dev->device_node;
> > +	/* Get configuration properties from device tree */
> > +	/* First, get register page */
> > +	ctrl = dev_request_mem_region(dev, 0);
> > +	if (IS_ERR(ctrl))
> > +		return -ENOMEM;
> 
> 		return PTR_ERR(ctrl);
> 

Okay, will fix those.


Thanks,
Steffen

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