add support for microchip 48l640 eeram connected via
SPI. Patch 1 introduces devicetree documentation
and patch 2 the driver.
Changes in v2:
as Rob helped, fix warnings from running command
'make DT_CHECKER_FLAGS=-m dt_binding_check'
- fix build warnings
- add Fabios Tested-by
Heiko Schocher (2):
mtd: devices: add devicetree documentation for microchip 48l640
mtd: devices: add support for microchip 48l640 EERAM
.../bindings/mtd/microchip,mchp48l640.yaml | 45 +++
drivers/mtd/devices/Kconfig | 6 +
drivers/mtd/devices/Makefile | 1 +
drivers/mtd/devices/mchp48l640.c | 374 ++++++++++++++++++
4 files changed, 426 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mtd/microchip,mchp48l640.yaml
create mode 100644 drivers/mtd/devices/mchp48l640.c
--
2.30.2
The Microchip 48l640 is a 8KByte EERAM connected via SPI.
Add devicetree bindings documentation.
Signed-off-by: Heiko Schocher <[email protected]>
---
Changes in v2:
as Rob helped, fix warnings from running command
'make DT_CHECKER_FLAGS=-m dt_binding_check'
.../bindings/mtd/microchip,mchp48l640.yaml | 45 +++++++++++++++++++
1 file changed, 45 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mtd/microchip,mchp48l640.yaml
diff --git a/Documentation/devicetree/bindings/mtd/microchip,mchp48l640.yaml b/Documentation/devicetree/bindings/mtd/microchip,mchp48l640.yaml
new file mode 100644
index 0000000000000..08089f2db0761
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/microchip,mchp48l640.yaml
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/mtd/microchip,mchp48l640.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: MTD SPI driver for Microchip 48l640 (and similar) serial EERAM
+
+maintainers:
+ - Heiko Schocher <[email protected]>
+
+description: |
+ The Microchip 48l640 is a 8KByte EERAM connected via SPI.
+
+ datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/20006055B.pdf
+
+properties:
+ compatible:
+ items:
+ - const: microchip,48l640
+
+ reg:
+ maxItems: 1
+
+ spi-max-frequency: true
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ spi-eeram@0 {
+ compatible = "microchip,48l640";
+ reg = <0>;
+ spi-max-frequency = <20000000>;
+ };
+ };
+...
--
2.30.2
The Microchip 48l640 is a 8KByte EERAM connected via SPI.
Signed-off-by: Heiko Schocher <[email protected]>
Tested-by: Fabio Estevam <[email protected]>
---
I tried to use drivers/mtd/devices/mchp23k256.c but this
driver does not use any status register and there seems
slight differences in registers (no write enable register
for example), so I decided to make a new driver.
This driver sets the continuous mode bit in Status register,
which states you can write continuous ... but after writting
32 bytes the chip goes into an undefined state, so driver now
writes data in 32 byte chunks.
I also tried to use regmap, but it leads in a lot of more code,
and as this chip has only spi interface it makes no sense, or?
Tested this driver on board imx8mp-phyboard-pollux-rdk
board, which is already in mainline.
Made some tbot tests, which write at random offset random
length bytes with dd and and random content. Reread the data
after a reboot and compare with the written data. Works fine.
Changes in v2:
- fix build warnings
- add Fabios Tested-by
drivers/mtd/devices/Kconfig | 6 +
drivers/mtd/devices/Makefile | 1 +
drivers/mtd/devices/mchp48l640.c | 374 +++++++++++++++++++++++++++++++
3 files changed, 381 insertions(+)
create mode 100644 drivers/mtd/devices/mchp48l640.c
diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig
index 0f4c2d823de84..79cb981ececc9 100644
--- a/drivers/mtd/devices/Kconfig
+++ b/drivers/mtd/devices/Kconfig
@@ -89,6 +89,12 @@ config MTD_MCHP23K256
platform data, or a device tree description if you want to
specify device partitioning
+config MTD_MCHP48L640
+ tristate "Microchip 48L640 EERAM"
+ depends on SPI_MASTER
+ help
+ This enables access to Microchip 48L640 EERAM chips, using SPI.
+
config MTD_SPEAR_SMI
tristate "SPEAR MTD NOR Support through SMI controller"
depends on PLAT_SPEAR || COMPILE_TEST
diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile
index 991c8d12c0160..0362cf6bdc67f 100644
--- a/drivers/mtd/devices/Makefile
+++ b/drivers/mtd/devices/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_MTD_LART) += lart.o
obj-$(CONFIG_MTD_BLOCK2MTD) += block2mtd.o
obj-$(CONFIG_MTD_DATAFLASH) += mtd_dataflash.o
obj-$(CONFIG_MTD_MCHP23K256) += mchp23k256.o
+obj-$(CONFIG_MTD_MCHP48L640) += mchp48l640.o
obj-$(CONFIG_MTD_SPEAR_SMI) += spear_smi.o
obj-$(CONFIG_MTD_SST25L) += sst25l.o
obj-$(CONFIG_MTD_BCM47XXSFLASH) += bcm47xxsflash.o
diff --git a/drivers/mtd/devices/mchp48l640.c b/drivers/mtd/devices/mchp48l640.c
new file mode 100644
index 0000000000000..7b29b8c4e6fb2
--- /dev/null
+++ b/drivers/mtd/devices/mchp48l640.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Microchip 48L640 64 Kb SPI Serial EERAM
+ *
+ * Copyright Heiko Schocher <[email protected]>
+ *
+ * datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/20006055B.pdf
+ *
+ * we set continuous mode but reading/writing more bytes than
+ * pagesize seems to bring chip into state where readden values
+ * are wrong ... no idea why.
+ *
+ */
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/sizes.h>
+#include <linux/spi/flash.h>
+#include <linux/spi/spi.h>
+#include <linux/of_device.h>
+
+struct mchp48_caps {
+ unsigned int size;
+ unsigned int page_size;
+};
+
+struct mchp48l640_flash {
+ struct spi_device *spi;
+ struct mutex lock;
+ struct mtd_info mtd;
+ const struct mchp48_caps *caps;
+};
+
+#define MCHP48L640_CMD_WREN 0x06
+#define MCHP48L640_CMD_WRDI 0x04
+#define MCHP48L640_CMD_WRITE 0x02
+#define MCHP48L640_CMD_READ 0x03
+#define MCHP48L640_CMD_WRSR 0x01
+#define MCHP48L640_CMD_RDSR 0x05
+
+#define MCHP48L640_STATUS_RDY 0x01
+#define MCHP48L640_STATUS_WEL 0x02
+#define MCHP48L640_STATUS_BP0 0x04
+#define MCHP48L640_STATUS_BP1 0x08
+#define MCHP48L640_STATUS_SWM 0x10
+#define MCHP48L640_STATUS_PRO 0x20
+#define MCHP48L640_STATUS_ASE 0x40
+
+#define MCHP48L640_TIMEOUT 100
+
+#define MAX_CMD_SIZE 0x10
+
+#define to_mchp48l640_flash(x) container_of(x, struct mchp48l640_flash, mtd)
+
+static int mchp48l640_mkcmd(struct mchp48l640_flash *flash, u8 cmd, loff_t addr, char *buf)
+{
+ buf[0] = cmd;
+ buf[1] = addr >> 8;
+ buf[2] = addr;
+
+ return 3;
+}
+
+static int mchp48l640_read_status(struct mchp48l640_flash *flash, int *status)
+{
+ unsigned char cmd[2];
+ int ret;
+
+ cmd[0] = MCHP48L640_CMD_RDSR;
+ cmd[1] = 0x00;
+ mutex_lock(&flash->lock);
+ ret = spi_write_then_read(flash->spi, &cmd[0], 1, &cmd[1], 1);
+ mutex_unlock(&flash->lock);
+ if (!ret)
+ *status = cmd[1];
+ dev_dbg(&flash->spi->dev, "read status ret: %d status: %x", ret, *status);
+
+ return ret;
+}
+
+static int mchp48l640_waitforbit(struct mchp48l640_flash *flash, int bit, bool set)
+{
+ int ret, status;
+ unsigned long deadline;
+
+ deadline = jiffies + msecs_to_jiffies(MCHP48L640_TIMEOUT);
+ do {
+ ret = mchp48l640_read_status(flash, &status);
+ dev_dbg(&flash->spi->dev, "read status ret: %d bit: %x %sset status: %x",
+ ret, bit, (set ? "" : "not"), status);
+ if (ret)
+ return ret;
+
+ if (set) {
+ if ((status & bit) == bit)
+ return 0;
+ } else {
+ if ((status & bit) == 0)
+ return 0;
+ }
+
+ usleep_range(1000, 2000);
+ } while (!time_after_eq(jiffies, deadline));
+
+ dev_err(&flash->spi->dev, "Timeout waiting for bit %x %s set in status register.",
+ bit, (set ? "" : "not"));
+ return -ETIMEDOUT;
+}
+
+static int mchp48l640_write_prepare(struct mchp48l640_flash *flash, bool enable)
+{
+ unsigned char cmd[2];
+ int ret;
+
+ if (enable)
+ cmd[0] = MCHP48L640_CMD_WREN;
+ else
+ cmd[0] = MCHP48L640_CMD_WRDI;
+
+ mutex_lock(&flash->lock);
+ ret = spi_write(flash->spi, cmd, 1);
+ mutex_unlock(&flash->lock);
+
+ if (ret)
+ dev_err(&flash->spi->dev, "write %sable failed ret: %d",
+ (enable ? "en" : "dis"), ret);
+
+ dev_dbg(&flash->spi->dev, "write %sable success ret: %d",
+ (enable ? "en" : "dis"), ret);
+ if (enable)
+ return mchp48l640_waitforbit(flash, MCHP48L640_STATUS_WEL, true);
+
+ return ret;
+}
+
+static int mchp48l640_set_mode(struct mchp48l640_flash *flash)
+{
+ unsigned char cmd[2];
+ int ret;
+
+ ret = mchp48l640_write_prepare(flash, true);
+ if (ret)
+ return ret;
+
+ cmd[0] = MCHP48L640_CMD_WRSR;
+ cmd[1] = MCHP48L640_STATUS_PRO;
+
+ mutex_lock(&flash->lock);
+ ret = spi_write(flash->spi, cmd, 2);
+ mutex_unlock(&flash->lock);
+ if (ret)
+ dev_err(&flash->spi->dev, "Could not set continuous mode ret: %d", ret);
+
+ return mchp48l640_waitforbit(flash, MCHP48L640_STATUS_PRO, true);
+}
+
+static int mchp48l640_wait_rdy(struct mchp48l640_flash *flash)
+{
+ return mchp48l640_waitforbit(flash, MCHP48L640_STATUS_RDY, false);
+};
+
+static int mchp48l640_write_page(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const unsigned char *buf)
+{
+ struct mchp48l640_flash *flash = to_mchp48l640_flash(mtd);
+ unsigned char *cmd;
+ int ret;
+ int cmdlen;
+
+ cmd = kmalloc((3 + len), GFP_KERNEL | GFP_DMA);
+ if (!cmd)
+ return -ENOMEM;
+
+ ret = mchp48l640_wait_rdy(flash);
+ if (ret)
+ goto fail;
+
+ ret = mchp48l640_write_prepare(flash, true);
+ if (ret)
+ goto fail;
+
+ mutex_lock(&flash->lock);
+ cmdlen = mchp48l640_mkcmd(flash, MCHP48L640_CMD_WRITE, to, cmd);
+ memcpy(&cmd[cmdlen], buf, len);
+ ret = spi_write(flash->spi, cmd, cmdlen + len);
+ mutex_unlock(&flash->lock);
+ if (!ret)
+ *retlen += len;
+ else
+ goto fail;
+
+ ret = mchp48l640_waitforbit(flash, MCHP48L640_STATUS_WEL, false);
+ if (ret)
+ goto fail;
+
+ kfree(cmd);
+ return 0;
+fail:
+ kfree(cmd);
+ dev_err(&flash->spi->dev, "write fail with: %d", ret);
+ return ret;
+};
+
+static int mchp48l640_write(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const unsigned char *buf)
+{
+ struct mchp48l640_flash *flash = to_mchp48l640_flash(mtd);
+ int ret;
+ size_t wlen = 0;
+ loff_t woff = to;
+ size_t ws;
+ size_t page_sz = flash->caps->page_size;
+
+ /*
+ * we set PRO bit (page rollover), but writing length > page size
+ * does result in total chaos, so write in 32 byte chunks.
+ */
+ while (wlen < len) {
+ ws = min((len - wlen), page_sz);
+ ret = mchp48l640_write_page(mtd, woff, ws, retlen, &buf[wlen]);
+ if (ret)
+ return ret;
+ wlen += ws;
+ woff += ws;
+ }
+
+ return ret;
+}
+
+static int mchp48l640_read_page(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, unsigned char *buf)
+{
+ struct mchp48l640_flash *flash = to_mchp48l640_flash(mtd);
+ unsigned char *cmd;
+ int ret;
+ int cmdlen;
+
+ cmd = kmalloc((3 + len), GFP_KERNEL | GFP_DMA);
+ if (!cmd)
+ return -ENOMEM;
+
+ ret = mchp48l640_wait_rdy(flash);
+ if (ret)
+ goto fail;
+
+ mutex_lock(&flash->lock);
+ cmdlen = mchp48l640_mkcmd(flash, MCHP48L640_CMD_READ, from, cmd);
+ ret = spi_write_then_read(flash->spi, cmd, cmdlen, buf, len);
+ mutex_unlock(&flash->lock);
+ if (!ret)
+ *retlen += len;
+
+ return ret;
+
+fail:
+ kfree(cmd);
+ dev_err(&flash->spi->dev, "read fail with: %d", ret);
+ return ret;
+}
+
+static int mchp48l640_read(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, unsigned char *buf)
+{
+ struct mchp48l640_flash *flash = to_mchp48l640_flash(mtd);
+ int ret;
+ size_t wlen = 0;
+ loff_t woff = from;
+ size_t ws;
+ size_t page_sz = flash->caps->page_size;
+
+ /*
+ * we set PRO bit (page rollover), but if read length > page size
+ * does result in total chaos in result ...
+ */
+ dev_dbg(&flash->spi->dev, "read len: %ld from: %llx", len, from);
+ while (wlen < len) {
+ ws = min((len - wlen), page_sz);
+ ret = mchp48l640_read_page(mtd, woff, ws, retlen, &buf[wlen]);
+ if (ret)
+ return ret;
+ wlen += ws;
+ woff += ws;
+ }
+
+ return ret;
+};
+
+static const struct mchp48_caps mchp48l640_caps = {
+ .size = SZ_8K,
+ .page_size = 32,
+};
+
+static int mchp48l640_probe(struct spi_device *spi)
+{
+ struct mchp48l640_flash *flash;
+ struct flash_platform_data *data;
+ int err;
+ int status;
+
+ flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL);
+ if (!flash)
+ return -ENOMEM;
+
+ flash->spi = spi;
+ mutex_init(&flash->lock);
+ spi_set_drvdata(spi, flash);
+
+ err = mchp48l640_read_status(flash, &status);
+ if (err)
+ return err;
+
+ err = mchp48l640_set_mode(flash);
+ if (err)
+ return err;
+
+ data = dev_get_platdata(&spi->dev);
+
+ flash->caps = of_device_get_match_data(&spi->dev);
+ if (!flash->caps)
+ flash->caps = &mchp48l640_caps;
+
+ mtd_set_of_node(&flash->mtd, spi->dev.of_node);
+ flash->mtd.dev.parent = &spi->dev;
+ flash->mtd.type = MTD_RAM;
+ flash->mtd.flags = MTD_CAP_RAM;
+ flash->mtd.writesize = flash->caps->page_size;
+ flash->mtd.size = flash->caps->size;
+ flash->mtd._read = mchp48l640_read;
+ flash->mtd._write = mchp48l640_write;
+
+ err = mtd_device_register(&flash->mtd, data ? data->parts : NULL,
+ data ? data->nr_parts : 0);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+static int mchp48l640_remove(struct spi_device *spi)
+{
+ struct mchp48l640_flash *flash = spi_get_drvdata(spi);
+
+ return mtd_device_unregister(&flash->mtd);
+}
+
+static const struct of_device_id mchp48l640_of_table[] = {
+ {
+ .compatible = "microchip,48l640",
+ .data = &mchp48l640_caps,
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mchp48l640_of_table);
+
+static struct spi_driver mchp48l640_driver = {
+ .driver = {
+ .name = "mchp48l640",
+ .of_match_table = of_match_ptr(mchp48l640_of_table),
+ },
+ .probe = mchp48l640_probe,
+ .remove = mchp48l640_remove,
+};
+
+module_spi_driver(mchp48l640_driver);
+
+MODULE_DESCRIPTION("MTD SPI driver for Microchip 48l640 EERAM chips");
+MODULE_AUTHOR("Heiko Schocher <[email protected]>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("spi:mchp48l640");
--
2.30.2
Hi Heiko,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on mtd/mtd/next]
[also build test WARNING on mtd/mtd/fixes linux/master linus/master v5.13-rc3 next-20210528]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Heiko-Schocher/mtd-devices-add-support-for-microchip-48l640-EERAM/20210529-182943
base: https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/next
config: arc-allyesconfig (attached as .config)
compiler: arceb-elf-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/eccf3abb95a75cb12c0506c6db8d129b69c71a9c
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Heiko-Schocher/mtd-devices-add-support-for-microchip-48l640-EERAM/20210529-182943
git checkout eccf3abb95a75cb12c0506c6db8d129b69c71a9c
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
In file included from include/linux/printk.h:409,
from include/linux/kernel.h:17,
from include/linux/delay.h:22,
from drivers/mtd/devices/mchp48l640.c:14:
drivers/mtd/devices/mchp48l640.c: In function 'mchp48l640_read':
>> drivers/mtd/devices/mchp48l640.c:280:28: warning: format '%ld' expects argument of type 'long int', but argument 4 has type 'size_t' {aka 'unsigned int'} [-Wformat=]
280 | dev_dbg(&flash->spi->dev, "read len: %ld from: %llx", len, from);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/dynamic_debug.h:129:15: note: in definition of macro '__dynamic_func_call'
129 | func(&id, ##__VA_ARGS__); \
| ^~~~~~~~~~~
include/linux/dynamic_debug.h:161:2: note: in expansion of macro '_dynamic_func_call'
161 | _dynamic_func_call(fmt,__dynamic_dev_dbg, \
| ^~~~~~~~~~~~~~~~~~
include/linux/dev_printk.h:123:2: note: in expansion of macro 'dynamic_dev_dbg'
123 | dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~
include/linux/dev_printk.h:123:23: note: in expansion of macro 'dev_fmt'
123 | dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~~
drivers/mtd/devices/mchp48l640.c:280:2: note: in expansion of macro 'dev_dbg'
280 | dev_dbg(&flash->spi->dev, "read len: %ld from: %llx", len, from);
| ^~~~~~~
drivers/mtd/devices/mchp48l640.c:280:41: note: format string is defined here
280 | dev_dbg(&flash->spi->dev, "read len: %ld from: %llx", len, from);
| ~~^
| |
| long int
| %d
vim +280 drivers/mtd/devices/mchp48l640.c
265
266 static int mchp48l640_read(struct mtd_info *mtd, loff_t from, size_t len,
267 size_t *retlen, unsigned char *buf)
268 {
269 struct mchp48l640_flash *flash = to_mchp48l640_flash(mtd);
270 int ret;
271 size_t wlen = 0;
272 loff_t woff = from;
273 size_t ws;
274 size_t page_sz = flash->caps->page_size;
275
276 /*
277 * we set PRO bit (page rollover), but if read length > page size
278 * does result in total chaos in result ...
279 */
> 280 dev_dbg(&flash->spi->dev, "read len: %ld from: %llx", len, from);
281 while (wlen < len) {
282 ws = min((len - wlen), page_sz);
283 ret = mchp48l640_read_page(mtd, woff, ws, retlen, &buf[wlen]);
284 if (ret)
285 return ret;
286 wlen += ws;
287 woff += ws;
288 }
289
290 return ret;
291 };
292
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]