Commit 044ee8f8 authored by Evan Green's avatar Evan Green Committed by Greg Kroah-Hartman
Browse files

nvmem: qfprom: Don't touch certain fuses 



Some fuse ranges are protected by the XPU such that the AP cannot
access them. Attempting to do so causes an SError. Use the newly
introduced per-soc compatible string, and the newly introduced
nvmem keepout support to attach the set of regions
we should not access.

Reviewed-by: default avatarDouglas Anderson <dianders@chromium.org>
Signed-off-by: default avatarEvan Green <evgreen@chromium.org>
Signed-off-by: default avatarSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20201127102837.19366-5-srinivas.kandagatla@linaro.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c8b336bb

drivers/nvmem/qfprom.c

+30 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <linux/mod_devicetable.h>

#include <linux/nvmem-provider.h>

#include <linux/platform_device.h>

#include <linux/property.h>

#include <linux/regulator/consumer.h>



/* Blow timer clock frequency in Mhz */
@@ -88,6 +89,28 @@ struct qfprom_touched_values { 
	u32 timer_val;

};



/**

 * struct qfprom_soc_compatible_data - Data matched against the SoC

 * compatible string.

 *

 * @keepout: Array of keepout regions for this SoC.

 * @nkeepout: Number of elements in the keepout array.

 */

struct qfprom_soc_compatible_data {

	const struct nvmem_keepout *keepout;

	unsigned int nkeepout;

};



static const struct nvmem_keepout sc7180_qfprom_keepout[] = {

	{.start = 0x128, .end = 0x148},

	{.start = 0x220, .end = 0x228}

};



static const struct qfprom_soc_compatible_data sc7180_qfprom = {

	.keepout = sc7180_qfprom_keepout,

	.nkeepout = ARRAY_SIZE(sc7180_qfprom_keepout)

};



/**

 * qfprom_disable_fuse_blowing() - Undo enabling of fuse blowing.

 * @priv: Our driver data.
@@ -281,6 +304,7 @@ static int qfprom_probe(struct platform_device *pdev) 
	struct device *dev = &pdev->dev;

	struct resource *res;

	struct nvmem_device *nvmem;

	const struct qfprom_soc_compatible_data *soc_data;

	struct qfprom_priv *priv;

	int ret;
@@ -299,6 +323,11 @@ static int qfprom_probe(struct platform_device *pdev) 
	econfig.priv = priv;



	priv->dev = dev;

	soc_data = device_get_match_data(dev);

	if (soc_data) {

		econfig.keepout = soc_data->keepout;

		econfig.nkeepout = soc_data->nkeepout;

	}



	/*

	 * If more than one region is provided then the OS has the ability
@@ -354,6 +383,7 @@ static int qfprom_probe(struct platform_device *pdev) 


static const struct of_device_id qfprom_of_match[] = {

	{ .compatible = "qcom,qfprom",},

	{ .compatible = "qcom,sc7180-qfprom", .data = &sc7180_qfprom},

	{/* sentinel */},

};

MODULE_DEVICE_TABLE(of, qfprom_of_match);