Add generic i.MX8 SoC driver along with the i.MX8MQ SoC specific code.
For now, only i.MX8MQ revision B1 is supported. For any other, i.MX8MQ
revision it will print 'unknown'.
Signed-off-by: Abel Vesa <[email protected]>
---
drivers/soc/imx/Makefile | 1 +
drivers/soc/imx/soc-imx8.c | 115 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 116 insertions(+)
create mode 100644 drivers/soc/imx/soc-imx8.c
diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
index 506a6f3..d6b529e0 100644
--- a/drivers/soc/imx/Makefile
+++ b/drivers/soc/imx/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_HAVE_IMX_GPC) += gpc.o
obj-$(CONFIG_IMX_GPCV2_PM_DOMAINS) += gpcv2.o
+obj-$(CONFIG_ARCH_MXC) += soc-imx8.o
diff --git a/drivers/soc/imx/soc-imx8.c b/drivers/soc/imx/soc-imx8.c
new file mode 100644
index 0000000..fc6429f
--- /dev/null
+++ b/drivers/soc/imx/soc-imx8.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/sys_soc.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+
+#define REV_B1 0x21
+
+#define IMX8MQ_SW_INFO_B1 0x40
+#define IMX8MQ_SW_MAGIC_B1 0xff0055aa
+
+struct imx8_soc_data {
+ char *name;
+ u32 (*soc_revision)(void);
+};
+
+static u32 __init imx8mq_soc_revision(void)
+{
+ struct device_node *np;
+ void __iomem *ocotp_base;
+ u32 magic;
+ u32 rev = 0;
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,imx8mq-ocotp");
+ if (!np)
+ goto out;
+
+ ocotp_base = of_iomap(np, 0);
+ WARN_ON(!ocotp_base);
+
+ magic = readl_relaxed(ocotp_base + IMX8MQ_SW_INFO_B1);
+ if (magic == IMX8MQ_SW_MAGIC_B1)
+ rev = REV_B1;
+
+ iounmap(ocotp_base);
+
+out:
+ of_node_put(np);
+ return rev;
+}
+
+static const struct imx8_soc_data imx8mq_soc_data = {
+ .name = "i.MX8MQ",
+ .soc_revision = imx8mq_soc_revision,
+};
+
+static const struct of_device_id imx8_soc_match[] = {
+ { .compatible = "fsl,imx8mq", .data = &imx8mq_soc_data, },
+ { }
+};
+
+#define imx8_revision(soc_rev) \
+ soc_rev ? \
+ kasprintf(GFP_KERNEL, "%d.%d", (soc_rev >> 4) & 0xf, soc_rev & 0xf) : \
+ "unknown"
+
+static int __init imx8_soc_init(void)
+{
+ struct soc_device_attribute *soc_dev_attr;
+ struct soc_device *soc_dev;
+ struct device_node *root;
+ const struct of_device_id *id;
+ u32 soc_rev = 0;
+ const struct imx8_soc_data *data;
+ int ret;
+
+ soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
+ if (!soc_dev_attr)
+ return -ENODEV;
+
+ soc_dev_attr->family = "Freescale i.MX";
+
+ root = of_find_node_by_path("/");
+ ret = of_property_read_string(root, "model", &soc_dev_attr->machine);
+ if (ret)
+ goto free_soc;
+
+ id = of_match_node(imx8_soc_match, root);
+ if (!id)
+ goto free_soc;
+
+ of_node_put(root);
+
+ data = id->data;
+ if (data) {
+ soc_dev_attr->soc_id = data->name;
+ if (data->soc_revision)
+ soc_rev = data->soc_revision();
+ }
+
+ soc_dev_attr->revision = imx8_revision(soc_rev);
+ if (!soc_dev_attr->revision)
+ goto free_soc;
+
+ soc_dev = soc_device_register(soc_dev_attr);
+ if (IS_ERR(soc_dev))
+ goto free_rev;
+
+ return 0;
+
+free_rev:
+ kfree(soc_dev_attr->revision);
+free_soc:
+ kfree(soc_dev_attr);
+ of_node_put(root);
+ return -ENODEV;
+}
+device_initcall(imx8_soc_init);
--
2.7.4
On Fri, 2019-03-22 at 16:49 +0000, Abel Vesa wrote:
> Add generic i.MX8 SoC driver along with the i.MX8MQ SoC specific code.
> For now, only i.MX8MQ revision B1 is supported. For any other, i.MX8MQ
> revision it will print 'unknown'.
> +#define REV_B1 0x21
> +
> +#define IMX8MQ_SW_INFO_B1 0x40
> +#define IMX8MQ_SW_MAGIC_B1 0xff0055aa
> +
> + np = of_find_compatible_node(NULL, NULL, "fsl,imx8mq-ocotp");+
> + ocotp_base = of_iomap(np, 0);
> +
> + magic = readl_relaxed(ocotp_base + IMX8MQ_SW_INFO_B1);
> + if (magic == IMX8MQ_SW_MAGIC_B1)
> + rev = REV_B1;
This is based on ATF code in vendor tree, but shouldn't we have some
sort of explanation for this "magic"?
Looking at the OCOTP driver reg 0x40 is IMX_OCOTP_ADDR_DATA2 and it's
used as part of fuse writes. According to the driver code 8mq is
compatible with 7d and this write path is enabled for imx8mq-ocotp.
Looking at the OCOTP manual reg 0x40 is OCOTP_HW_OCOTP_READ_FUSE_DATA
and it's meant to be used together with IMX_OCOTP_ADDR_CTRL to read
info. Maybe my manual (rev0 2018-01) is incorrect?
Looking at the manual this will return the value of the fuse last
requested via IMX_OCOTP_ADDR_CTRL but no such request is made in this
driver. So reading from OCOTP 0x40 might return an unrelated value?!
The manual does document that fuse 0x440[3:0] is a "silicon revision
number"; maybe we should read that?
--
Regards,
Leonard
On 3/28/2019 6:43 PM, Leonard Crestez wrote:
> On Fri, 2019-03-22 at 16:49 +0000, Abel Vesa wrote:
>> Add generic i.MX8 SoC driver along with the i.MX8MQ SoC specific code.
>> For now, only i.MX8MQ revision B1 is supported. For any other, i.MX8MQ
>> revision it will print 'unknown'.
>
>> +#define REV_B1 0x21
>> +
>> +#define IMX8MQ_SW_INFO_B1 0x40
>> +#define IMX8MQ_SW_MAGIC_B1 0xff0055aa
>> +
>> + np = of_find_compatible_node(NULL, NULL, "fsl,imx8mq-ocotp");+
>> + ocotp_base = of_iomap(np, 0);
>> +
>> + magic = readl_relaxed(ocotp_base + IMX8MQ_SW_INFO_B1);
>> + if (magic == IMX8MQ_SW_MAGIC_B1)
>> + rev = REV_B1;
>
> This is based on ATF code in vendor tree, but shouldn't we have some
> sort of explanation for this "magic"?
>
> Looking at the OCOTP driver reg 0x40 is IMX_OCOTP_ADDR_DATA2 and it's
> used as part of fuse writes. According to the driver code 8mq is
> compatible with 7d and this write path is enabled for imx8mq-ocotp.
After further digging in NXP manuals and uboot sources it seems that
imx8mq ocotp is like imx6 rather than imx7. Posted fix for nvmem driver:
https://patchwork.kernel.org/patch/10908081/
Reviewed-by: Leonard Crestez <[email protected]>
It might still be nice to find a way to identify imx8mq B0.
On Fri, Mar 22, 2019 at 04:49:20PM +0000, Abel Vesa wrote:
> Add generic i.MX8 SoC driver along with the i.MX8MQ SoC specific code.
> For now, only i.MX8MQ revision B1 is supported. For any other, i.MX8MQ
> revision it will print 'unknown'.
>
> Signed-off-by: Abel Vesa <[email protected]>
Applied, thanks.