On 11/15/20 12:03 PM, Moritz Fischer wrote: > On Fri, Nov 13, 2020 at 04:55:56PM -0800, Russ Weight wrote: >> Extend the MAX10 BMC Secure Update driver to provide a >> sysfs file to expose the flash update count for the FPGA >> user image. >> >> Signed-off-by: Russ Weight <[email protected]> >> Reviewed-by: Tom Rix <[email protected]> >> --- >> v5: >> - Renamed sysfs node user_flash_count to flash_count and updated the >> sysfs documentation accordingly. >> v4: >> - Moved the sysfs file for displaying the flash count from the >> FPGA Security Manager class driver to here. The >> m10bmc_user_flash_count() function is removed and the >> functionality is moved into a user_flash_count_show() >> function. >> - Added ABI documentation for the new sysfs entry >> v3: >> - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_ >> - Changed "MAX10 BMC Secure Engine driver" to "MAX10 BMC Secure Update >> driver" >> - Removed wrapper functions (m10bmc_raw_*, m10bmc_sys_*). The >> underlying functions are now called directly. >> v2: >> - Renamed get_qspi_flash_count() to m10bmc_user_flash_count() >> - Minor code cleanup per review comments >> - Added m10bmc_ prefix to functions in m10bmc_iops structure >> --- >> .../testing/sysfs-driver-intel-m10-bmc-secure | 8 +++++ >> drivers/fpga/intel-m10-bmc-secure.c | 34 +++++++++++++++++++ >> 2 files changed, 42 insertions(+) >> >> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure >> b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure >> index 2992488b717a..73a3aba750e8 100644 >> --- a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure >> +++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-secure >> @@ -27,3 +27,11 @@ Description: Read only. Returns the root entry hash >> for the BMC image >> "hash not programmed". This file is only visible if the >> underlying device supports it. >> Format: "0x%x". >> + >> +What: >> /sys/bus/platform/devices/n3000bmc-secure.*.auto/security/flash_count >> +Date: Oct 2020 >> +KernelVersion: 5.11 >> +Contact: Russ Weight <[email protected]> >> +Description: Read only. Returns number of times the secure update >> + staging area has been flashed. >> + Format: "%u". >> diff --git a/drivers/fpga/intel-m10-bmc-secure.c >> b/drivers/fpga/intel-m10-bmc-secure.c >> index 198bc8273d6b..6ad897001086 100644 >> --- a/drivers/fpga/intel-m10-bmc-secure.c >> +++ b/drivers/fpga/intel-m10-bmc-secure.c >> @@ -11,6 +11,7 @@ >> #include <linux/mfd/intel-m10-bmc.h> >> #include <linux/module.h> >> #include <linux/platform_device.h> >> +#include <linux/slab.h> >> >> struct m10bmc_sec { >> struct device *dev; >> @@ -77,7 +78,40 @@ DEVICE_ATTR_SEC_REH_RO(bmc, BMC_PROG_MAGIC, >> BMC_PROG_ADDR, BMC_REH_ADDR); >> DEVICE_ATTR_SEC_REH_RO(sr, SR_PROG_MAGIC, SR_PROG_ADDR, SR_REH_ADDR); >> DEVICE_ATTR_SEC_REH_RO(pr, PR_PROG_MAGIC, PR_PROG_ADDR, PR_REH_ADDR); >> >> +#define FLASH_COUNT_SIZE 4096 /* count stored as inverted bit vector >> */ >> + >> +static ssize_t flash_count_show(struct device *dev, >> + struct device_attribute *attr, char *buf) >> +{ >> + struct m10bmc_sec *sec = dev_get_drvdata(dev); >> + unsigned int stride = regmap_get_reg_stride(sec->m10bmc->regmap); >> + unsigned int num_bits = FLASH_COUNT_SIZE * 8; >> + u8 *flash_buf; >> + int cnt, ret; > (Nit) Can you make this: > > struct m10bmc_sec *sec = dev_get_drvdata(dev); > unsigned int stride, num_bits; > u8 *flash_buf; > int cnt, ret; > > stride = regmap_get_reg_stride(sec->m10bmc->regmap); > num_bits = FLASH_COUNT_SIZE * 8; Sure - I'll make the change. Thanks, - Russ > > >> + >> + flash_buf = kmalloc(FLASH_COUNT_SIZE, GFP_KERNEL); >> + if (!flash_buf) >> + return -ENOMEM; >> + >> + ret = regmap_bulk_read(sec->m10bmc->regmap, STAGING_FLASH_COUNT, >> + flash_buf, FLASH_COUNT_SIZE / stride); >> + if (ret) { >> + dev_err(sec->dev, >> + "failed to read flash count: %x cnt %x: %d\n", >> + STAGING_FLASH_COUNT, FLASH_COUNT_SIZE / stride, ret); >> + goto exit_free; >> + } >> + cnt = num_bits - bitmap_weight((unsigned long *)flash_buf, num_bits); >> + >> +exit_free: >> + kfree(flash_buf); >> + >> + return ret ? : sysfs_emit(buf, "%u\n", cnt); >> +} >> +static DEVICE_ATTR_RO(flash_count); >> + >> static struct attribute *m10bmc_security_attrs[] = { >> + &dev_attr_flash_count.attr, >> &dev_attr_bmc_root_entry_hash.attr, >> &dev_attr_sr_root_entry_hash.attr, >> &dev_attr_pr_root_entry_hash.attr, >> -- >> 2.25.1 >> > Otherwise looks good to me, > > - Moritz
