diff mbox series

[v1] mtd: rawnand: macronix: OTP access for MX30LFxG18AC

Message ID 20230426072455.3887717-1-AVKrasnov@sberdevices.ru (mailing list archive)
State New, archived
Headers show
Series [v1] mtd: rawnand: macronix: OTP access for MX30LFxG18AC | expand

Commit Message

Arseniy Krasnov April 26, 2023, 7:24 a.m. UTC
This adds support for OTP area access on MX30LFxG18AC chip series.

Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
---
 drivers/mtd/nand/raw/nand_macronix.c | 212 +++++++++++++++++++++++++++
 1 file changed, 212 insertions(+)

Comments

kernel test robot April 26, 2023, 9:21 a.m. UTC | #1
Hi Arseniy,

kernel test robot noticed the following build errors:

[auto build test ERROR on mtd/nand/next]
[also build test ERROR on linus/master v6.3 next-20230425]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Arseniy-Krasnov/mtd-rawnand-macronix-OTP-access-for-MX30LFxG18AC/20230426-153143
base:   https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next
patch link:    https://lore.kernel.org/r/20230426072455.3887717-1-AVKrasnov%40sberdevices.ru
patch subject: [PATCH v1] mtd: rawnand: macronix: OTP access for MX30LFxG18AC
config: m68k-allyesconfig (https://download.01.org/0day-ci/archive/20230426/202304261704.eyrD5KVk-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 12.1.0
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/intel-lab-lkp/linux/commit/3529f3465e99379489b59c035a8a0506c3756ef4
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Arseniy-Krasnov/mtd-rawnand-macronix-OTP-access-for-MX30LFxG18AC/20230426-153143
        git checkout 3529f3465e99379489b59c035a8a0506c3756ef4
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=m68k olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=m68k SHELL=/bin/bash drivers/mtd/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304261704.eyrD5KVk-lkp@intel.com/

All error/warnings (new ones prefixed by >>):

   drivers/mtd/nand/raw/nand_macronix.c: In function '__macronix_30lfxg18ac_rw_otp':
>> drivers/mtd/nand/raw/nand_macronix.c:384:19: error: implicit declaration of function 'kmalloc'; did you mean 'mm_alloc'? [-Werror=implicit-function-declaration]
     384 |         dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
         |                   ^~~~~~~
         |                   mm_alloc
>> drivers/mtd/nand/raw/nand_macronix.c:384:17: warning: assignment to 'void *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
     384 |         dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
         |                 ^
>> drivers/mtd/nand/raw/nand_macronix.c:437:9: error: implicit declaration of function 'kfree'; did you mean 'kvfree'? [-Werror=implicit-function-declaration]
     437 |         kfree(dma_buf);
         |         ^~~~~
         |         kvfree
   cc1: some warnings being treated as errors


vim +384 drivers/mtd/nand/raw/nand_macronix.c

   366	
   367	static int __macronix_30lfxg18ac_rw_otp(struct mtd_info *mtd,
   368						loff_t offs_in_flash,
   369						size_t len, size_t *retlen,
   370						u_char *buf, bool write)
   371	{
   372		struct nand_chip *nand;
   373		size_t bytes_handled;
   374		unsigned long page;
   375		off_t offs_in_page;
   376		void *dma_buf;
   377		int ret;
   378	
   379		/* 'nand_prog/read_page_op()' may use 'buf' as DMA buffer,
   380		 * so allocate properly aligned memory for it. This is
   381		 * needed because cross page accesses may lead to unaligned
   382		 * buffer address for DMA.
   383		 */
 > 384		dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
   385		if (!dma_buf)
   386			return -ENOMEM;
   387	
   388		nand = mtd_to_nand(mtd);
   389		nand_select_target(nand, 0);
   390	
   391		ret = macronix_30lfxg18ac_otp_enable(nand);
   392		if (ret)
   393			goto out_otp;
   394	
   395		page = offs_in_flash;
   396		/* 'page' will be result of division. */
   397		offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
   398		bytes_handled = 0;
   399	
   400		while (bytes_handled < len &&
   401		       page < MACRONIX_30LFXG18AC_OTP_PAGES) {
   402			size_t bytes_to_handle;
   403	
   404			bytes_to_handle = min_t(size_t, len - bytes_handled,
   405						MACRONIX_30LFXG18AC_OTP_PAGE_SIZE -
   406						offs_in_page);
   407	
   408			if (write) {
   409				memcpy(dma_buf, &buf[bytes_handled], bytes_to_handle);
   410				ret = nand_prog_page_op(nand, page, offs_in_page,
   411							dma_buf, bytes_to_handle);
   412			} else {
   413				ret = nand_read_page_op(nand, page, offs_in_page,
   414							dma_buf, bytes_to_handle);
   415				if (!ret)
   416					memcpy(&buf[bytes_handled], dma_buf,
   417					       bytes_to_handle);
   418			}
   419			if (ret)
   420				goto out_otp;
   421	
   422			bytes_handled += bytes_to_handle;
   423			offs_in_page = 0;
   424			page++;
   425		}
   426	
   427		*retlen = bytes_handled;
   428	
   429	out_otp:
   430		if (ret)
   431			dev_err(&mtd->dev, "failed to perform OTP IO: %i\n", ret);
   432	
   433		ret = macronix_30lfxg18ac_otp_disable(nand);
   434		WARN(ret, "failed to leave OTP mode after %s\n",
   435		     write ? "write" : "read");
   436		nand_deselect_target(nand);
 > 437		kfree(dma_buf);
   438	
   439		return ret;
   440	}
   441
kernel test robot April 26, 2023, 1:06 p.m. UTC | #2
Hi Arseniy,

kernel test robot noticed the following build errors:

[auto build test ERROR on mtd/nand/next]
[also build test ERROR on linus/master v6.3 next-20230425]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Arseniy-Krasnov/mtd-rawnand-macronix-OTP-access-for-MX30LFxG18AC/20230426-153143
base:   https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next
patch link:    https://lore.kernel.org/r/20230426072455.3887717-1-AVKrasnov%40sberdevices.ru
patch subject: [PATCH v1] mtd: rawnand: macronix: OTP access for MX30LFxG18AC
config: i386-randconfig-a001-20230424 (https://download.01.org/0day-ci/archive/20230426/202304262003.Lzpyh2BA-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
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/intel-lab-lkp/linux/commit/3529f3465e99379489b59c035a8a0506c3756ef4
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Arseniy-Krasnov/mtd-rawnand-macronix-OTP-access-for-MX30LFxG18AC/20230426-153143
        git checkout 3529f3465e99379489b59c035a8a0506c3756ef4
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/mtd/nand/raw/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304262003.Lzpyh2BA-lkp@intel.com/

All error/warnings (new ones prefixed by >>):

>> drivers/mtd/nand/raw/nand_macronix.c:384:12: error: implicit declaration of function 'kmalloc' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
           dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
                     ^
   drivers/mtd/nand/raw/nand_macronix.c:384:12: note: did you mean 'mm_alloc'?
   include/linux/sched/mm.h:16:26: note: 'mm_alloc' declared here
   extern struct mm_struct *mm_alloc(void);
                            ^
>> drivers/mtd/nand/raw/nand_macronix.c:384:10: warning: incompatible integer to pointer conversion assigning to 'void *' from 'int' [-Wint-conversion]
           dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
                   ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/mtd/nand/raw/nand_macronix.c:437:2: error: implicit declaration of function 'kfree' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
           kfree(dma_buf);
           ^
   1 warning and 2 errors generated.


vim +/kmalloc +384 drivers/mtd/nand/raw/nand_macronix.c

   366	
   367	static int __macronix_30lfxg18ac_rw_otp(struct mtd_info *mtd,
   368						loff_t offs_in_flash,
   369						size_t len, size_t *retlen,
   370						u_char *buf, bool write)
   371	{
   372		struct nand_chip *nand;
   373		size_t bytes_handled;
   374		unsigned long page;
   375		off_t offs_in_page;
   376		void *dma_buf;
   377		int ret;
   378	
   379		/* 'nand_prog/read_page_op()' may use 'buf' as DMA buffer,
   380		 * so allocate properly aligned memory for it. This is
   381		 * needed because cross page accesses may lead to unaligned
   382		 * buffer address for DMA.
   383		 */
 > 384		dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
   385		if (!dma_buf)
   386			return -ENOMEM;
   387	
   388		nand = mtd_to_nand(mtd);
   389		nand_select_target(nand, 0);
   390	
   391		ret = macronix_30lfxg18ac_otp_enable(nand);
   392		if (ret)
   393			goto out_otp;
   394	
   395		page = offs_in_flash;
   396		/* 'page' will be result of division. */
   397		offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
   398		bytes_handled = 0;
   399	
   400		while (bytes_handled < len &&
   401		       page < MACRONIX_30LFXG18AC_OTP_PAGES) {
   402			size_t bytes_to_handle;
   403	
   404			bytes_to_handle = min_t(size_t, len - bytes_handled,
   405						MACRONIX_30LFXG18AC_OTP_PAGE_SIZE -
   406						offs_in_page);
   407	
   408			if (write) {
   409				memcpy(dma_buf, &buf[bytes_handled], bytes_to_handle);
   410				ret = nand_prog_page_op(nand, page, offs_in_page,
   411							dma_buf, bytes_to_handle);
   412			} else {
   413				ret = nand_read_page_op(nand, page, offs_in_page,
   414							dma_buf, bytes_to_handle);
   415				if (!ret)
   416					memcpy(&buf[bytes_handled], dma_buf,
   417					       bytes_to_handle);
   418			}
   419			if (ret)
   420				goto out_otp;
   421	
   422			bytes_handled += bytes_to_handle;
   423			offs_in_page = 0;
   424			page++;
   425		}
   426	
   427		*retlen = bytes_handled;
   428	
   429	out_otp:
   430		if (ret)
   431			dev_err(&mtd->dev, "failed to perform OTP IO: %i\n", ret);
   432	
   433		ret = macronix_30lfxg18ac_otp_disable(nand);
   434		WARN(ret, "failed to leave OTP mode after %s\n",
   435		     write ? "write" : "read");
   436		nand_deselect_target(nand);
 > 437		kfree(dma_buf);
   438	
   439		return ret;
   440	}
   441
kernel test robot April 26, 2023, 1:37 p.m. UTC | #3
Hi Arseniy,

kernel test robot noticed the following build errors:

[auto build test ERROR on mtd/nand/next]
[also build test ERROR on linus/master v6.3 next-20230425]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Arseniy-Krasnov/mtd-rawnand-macronix-OTP-access-for-MX30LFxG18AC/20230426-153143
base:   https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next
patch link:    https://lore.kernel.org/r/20230426072455.3887717-1-AVKrasnov%40sberdevices.ru
patch subject: [PATCH v1] mtd: rawnand: macronix: OTP access for MX30LFxG18AC
config: hexagon-randconfig-r041-20230425 (https://download.01.org/0day-ci/archive/20230426/202304262101.pP2ae1ol-lkp@intel.com/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 437b7602e4a998220871de78afcb020b9c14a661)
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/intel-lab-lkp/linux/commit/3529f3465e99379489b59c035a8a0506c3756ef4
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Arseniy-Krasnov/mtd-rawnand-macronix-OTP-access-for-MX30LFxG18AC/20230426-153143
        git checkout 3529f3465e99379489b59c035a8a0506c3756ef4
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/mtd/nand/raw/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304262101.pP2ae1ol-lkp@intel.com/

All error/warnings (new ones prefixed by >>):

>> drivers/mtd/nand/raw/nand_macronix.c:384:12: error: call to undeclared function 'kmalloc'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
           dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
                     ^
   drivers/mtd/nand/raw/nand_macronix.c:384:12: note: did you mean 'mm_alloc'?
   include/linux/sched/mm.h:16:26: note: 'mm_alloc' declared here
   extern struct mm_struct *mm_alloc(void);
                            ^
>> drivers/mtd/nand/raw/nand_macronix.c:384:10: error: incompatible integer to pointer conversion assigning to 'void *' from 'int' [-Wint-conversion]
           dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
                   ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/mtd/nand/raw/nand_macronix.c:397:17: warning: comparison of distinct pointer types ('typeof ((page)) *' (aka 'unsigned long *') and 'uint64_t *' (aka 'unsigned long long *')) [-Wcompare-distinct-pointer-types]
           offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/asm-generic/div64.h:222:28: note: expanded from macro 'do_div'
           (void)(((typeof((n)) *)0) == ((uint64_t *)0));  \
                  ~~~~~~~~~~~~~~~~~~ ^  ~~~~~~~~~~~~~~~
>> drivers/mtd/nand/raw/nand_macronix.c:397:17: error: incompatible pointer types passing 'unsigned long *' to parameter of type 'uint64_t *' (aka 'unsigned long long *') [-Werror,-Wincompatible-pointer-types]
           offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/asm-generic/div64.h:238:22: note: expanded from macro 'do_div'
                   __rem = __div64_32(&(n), __base);       \
                                      ^~~~
   include/asm-generic/div64.h:213:38: note: passing argument to parameter 'dividend' here
   extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
                                        ^
>> drivers/mtd/nand/raw/nand_macronix.c:437:2: error: call to undeclared function 'kfree'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
           kfree(dma_buf);
           ^
   drivers/mtd/nand/raw/nand_macronix.c:437:2: note: did you mean 'kvfree'?
   include/linux/rcutiny.h:99:13: note: 'kvfree' declared here
   extern void kvfree(const void *addr);
               ^
>> drivers/mtd/nand/raw/nand_macronix.c:397:17: warning: shift count >= width of type [-Wshift-count-overflow]
           offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/asm-generic/div64.h:234:25: note: expanded from macro 'do_div'
           } else if (likely(((n) >> 32) == 0)) {          \
                                  ^  ~~
   include/linux/compiler.h:77:40: note: expanded from macro 'likely'
   # define likely(x)      __builtin_expect(!!(x), 1)
                                               ^
   2 warnings and 4 errors generated.


vim +/kmalloc +384 drivers/mtd/nand/raw/nand_macronix.c

   366	
   367	static int __macronix_30lfxg18ac_rw_otp(struct mtd_info *mtd,
   368						loff_t offs_in_flash,
   369						size_t len, size_t *retlen,
   370						u_char *buf, bool write)
   371	{
   372		struct nand_chip *nand;
   373		size_t bytes_handled;
   374		unsigned long page;
   375		off_t offs_in_page;
   376		void *dma_buf;
   377		int ret;
   378	
   379		/* 'nand_prog/read_page_op()' may use 'buf' as DMA buffer,
   380		 * so allocate properly aligned memory for it. This is
   381		 * needed because cross page accesses may lead to unaligned
   382		 * buffer address for DMA.
   383		 */
 > 384		dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
   385		if (!dma_buf)
   386			return -ENOMEM;
   387	
   388		nand = mtd_to_nand(mtd);
   389		nand_select_target(nand, 0);
   390	
   391		ret = macronix_30lfxg18ac_otp_enable(nand);
   392		if (ret)
   393			goto out_otp;
   394	
   395		page = offs_in_flash;
   396		/* 'page' will be result of division. */
 > 397		offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
   398		bytes_handled = 0;
   399	
   400		while (bytes_handled < len &&
   401		       page < MACRONIX_30LFXG18AC_OTP_PAGES) {
   402			size_t bytes_to_handle;
   403	
   404			bytes_to_handle = min_t(size_t, len - bytes_handled,
   405						MACRONIX_30LFXG18AC_OTP_PAGE_SIZE -
   406						offs_in_page);
   407	
   408			if (write) {
   409				memcpy(dma_buf, &buf[bytes_handled], bytes_to_handle);
   410				ret = nand_prog_page_op(nand, page, offs_in_page,
   411							dma_buf, bytes_to_handle);
   412			} else {
   413				ret = nand_read_page_op(nand, page, offs_in_page,
   414							dma_buf, bytes_to_handle);
   415				if (!ret)
   416					memcpy(&buf[bytes_handled], dma_buf,
   417					       bytes_to_handle);
   418			}
   419			if (ret)
   420				goto out_otp;
   421	
   422			bytes_handled += bytes_to_handle;
   423			offs_in_page = 0;
   424			page++;
   425		}
   426	
   427		*retlen = bytes_handled;
   428	
   429	out_otp:
   430		if (ret)
   431			dev_err(&mtd->dev, "failed to perform OTP IO: %i\n", ret);
   432	
   433		ret = macronix_30lfxg18ac_otp_disable(nand);
   434		WARN(ret, "failed to leave OTP mode after %s\n",
   435		     write ? "write" : "read");
   436		nand_deselect_target(nand);
 > 437		kfree(dma_buf);
   438	
   439		return ret;
   440	}
   441
diff mbox series

Patch

diff --git a/drivers/mtd/nand/raw/nand_macronix.c b/drivers/mtd/nand/raw/nand_macronix.c
index 1472f925f386..c0d12979933a 100644
--- a/drivers/mtd/nand/raw/nand_macronix.c
+++ b/drivers/mtd/nand/raw/nand_macronix.c
@@ -31,6 +31,20 @@ 
 
 #define MXIC_CMD_POWER_DOWN 0xB9
 
+#define ONFI_FEATURE_ADDR_30LFXG18AC_OTP	0x90
+#define MACRONIX_30LFXG18AC_OTP_START_PAGE	0
+#define MACRONIX_30LFXG18AC_OTP_PAGES		30
+#define MACRONIX_30LFXG18AC_OTP_PAGE_SIZE	2112
+#define MACRONIX_30LFXG18AC_OTP_START_BYTE	\
+	(MACRONIX_30LFXG18AC_OTP_START_PAGE *	\
+	 MACRONIX_30LFXG18AC_OTP_PAGE_SIZE)
+#define MACRONIX_30LFXG18AC_OTP_SIZE_BYTES	\
+	(MACRONIX_30LFXG18AC_OTP_PAGES *	\
+	 MACRONIX_30LFXG18AC_OTP_PAGE_SIZE)
+
+#define MACRONIX_30LFXG18AC_OTP_EN		BIT(0)
+#define MACRONIX_30LFXG18AC_OTP_LOCKED		BIT(1)
+
 struct nand_onfi_vendor_macronix {
 	u8 reserved;
 	u8 reliability_func;
@@ -316,6 +330,203 @@  static void macronix_nand_deep_power_down_support(struct nand_chip *chip)
 	chip->ops.resume = mxic_nand_resume;
 }
 
+static int macronix_30lfxg18ac_get_otp_info(struct mtd_info *mtd, size_t len,
+					    size_t *retlen,
+					    struct otp_info *buf)
+{
+	if (len < sizeof(*buf))
+		return -EINVAL;
+
+	/* Don't know how to check that OTP is locked. */
+	buf->locked = 0;
+	buf->start = MACRONIX_30LFXG18AC_OTP_START_BYTE;
+	buf->length = MACRONIX_30LFXG18AC_OTP_SIZE_BYTES;
+
+	*retlen = sizeof(*buf);
+
+	return 0;
+}
+
+static int macronix_30lfxg18ac_otp_enable(struct nand_chip *nand)
+{
+	uint8_t feature_buf[ONFI_SUBFEATURE_PARAM_LEN] = { 0 };
+
+	feature_buf[0] = MACRONIX_30LFXG18AC_OTP_EN;
+	return nand_set_features(nand, ONFI_FEATURE_ADDR_30LFXG18AC_OTP,
+				 feature_buf);
+}
+
+static int macronix_30lfxg18ac_otp_disable(struct nand_chip *nand)
+{
+	uint8_t feature_buf[ONFI_SUBFEATURE_PARAM_LEN] = { 0 };
+
+	return nand_set_features(nand, ONFI_FEATURE_ADDR_30LFXG18AC_OTP,
+				 feature_buf);
+}
+
+static int __macronix_30lfxg18ac_rw_otp(struct mtd_info *mtd,
+					loff_t offs_in_flash,
+					size_t len, size_t *retlen,
+					u_char *buf, bool write)
+{
+	struct nand_chip *nand;
+	size_t bytes_handled;
+	unsigned long page;
+	off_t offs_in_page;
+	void *dma_buf;
+	int ret;
+
+	/* 'nand_prog/read_page_op()' may use 'buf' as DMA buffer,
+	 * so allocate properly aligned memory for it. This is
+	 * needed because cross page accesses may lead to unaligned
+	 * buffer address for DMA.
+	 */
+	dma_buf = kmalloc(MACRONIX_30LFXG18AC_OTP_PAGE_SIZE, GFP_KERNEL);
+	if (!dma_buf)
+		return -ENOMEM;
+
+	nand = mtd_to_nand(mtd);
+	nand_select_target(nand, 0);
+
+	ret = macronix_30lfxg18ac_otp_enable(nand);
+	if (ret)
+		goto out_otp;
+
+	page = offs_in_flash;
+	/* 'page' will be result of division. */
+	offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
+	bytes_handled = 0;
+
+	while (bytes_handled < len &&
+	       page < MACRONIX_30LFXG18AC_OTP_PAGES) {
+		size_t bytes_to_handle;
+
+		bytes_to_handle = min_t(size_t, len - bytes_handled,
+					MACRONIX_30LFXG18AC_OTP_PAGE_SIZE -
+					offs_in_page);
+
+		if (write) {
+			memcpy(dma_buf, &buf[bytes_handled], bytes_to_handle);
+			ret = nand_prog_page_op(nand, page, offs_in_page,
+						dma_buf, bytes_to_handle);
+		} else {
+			ret = nand_read_page_op(nand, page, offs_in_page,
+						dma_buf, bytes_to_handle);
+			if (!ret)
+				memcpy(&buf[bytes_handled], dma_buf,
+				       bytes_to_handle);
+		}
+		if (ret)
+			goto out_otp;
+
+		bytes_handled += bytes_to_handle;
+		offs_in_page = 0;
+		page++;
+	}
+
+	*retlen = bytes_handled;
+
+out_otp:
+	if (ret)
+		dev_err(&mtd->dev, "failed to perform OTP IO: %i\n", ret);
+
+	ret = macronix_30lfxg18ac_otp_disable(nand);
+	WARN(ret, "failed to leave OTP mode after %s\n",
+	     write ? "write" : "read");
+	nand_deselect_target(nand);
+	kfree(dma_buf);
+
+	return ret;
+}
+
+static int macronix_30lfxg18ac_write_otp(struct mtd_info *mtd, loff_t to,
+					 size_t len, size_t *rlen,
+					 const u_char *buf)
+{
+	return __macronix_30lfxg18ac_rw_otp(mtd, to, len, rlen, (u_char *)buf,
+					    true);
+}
+
+static int macronix_30lfxg18ac_read_otp(struct mtd_info *mtd, loff_t from,
+					size_t len, size_t *rlen,
+					u_char *buf)
+{
+	return __macronix_30lfxg18ac_rw_otp(mtd, from, len, rlen, buf, false);
+}
+
+static int macronix_30lfxg18ac_lock_otp(struct mtd_info *mtd, loff_t from,
+					size_t len)
+{
+	uint8_t feature_buf[ONFI_SUBFEATURE_PARAM_LEN] = { 0 };
+	struct nand_chip *nand;
+	int ret;
+
+	if (from != MACRONIX_30LFXG18AC_OTP_START_BYTE ||
+	    len != MACRONIX_30LFXG18AC_OTP_SIZE_BYTES)
+		return -EINVAL;
+
+	dev_dbg(&mtd->dev, "locking OTP\n");
+
+	nand = mtd_to_nand(mtd);
+	nand_select_target(nand, 0);
+
+	feature_buf[0] = MACRONIX_30LFXG18AC_OTP_EN |
+			 MACRONIX_30LFXG18AC_OTP_LOCKED;
+	ret = nand_set_features(nand, ONFI_FEATURE_ADDR_30LFXG18AC_OTP,
+				feature_buf);
+	if (ret) {
+		dev_err(&mtd->dev,
+			"failed to lock OTP (set features): %i\n", ret);
+		nand_deselect_target(nand);
+		return ret;
+	}
+
+	/* Do dummy page prog with zero address. */
+	feature_buf[0] = 0;
+	ret = nand_prog_page_op(nand, 0, 0, feature_buf, 1);
+	if (ret)
+		dev_err(&mtd->dev,
+			"failed to lock OTP (page prog): %i\n", ret);
+
+	ret = macronix_30lfxg18ac_otp_disable(nand);
+	WARN(ret, "failed to leave OTP mode after lock\n");
+
+	nand_deselect_target(nand);
+
+	return ret;
+}
+
+static void macronix_nand_setup_otp(struct nand_chip *chip)
+{
+	static const char * const supported_otp_models[] = {
+		"MX30LF1G18AC",
+		"MX30LF2G18AC",
+		"MX30LF4G18AC",
+	};
+	struct mtd_info *mtd;
+
+	if (!chip->parameters.supports_set_get_features)
+		return;
+
+	if (match_string(supported_otp_models,
+			 ARRAY_SIZE(supported_otp_models),
+			 chip->parameters.model) < 0)
+		return;
+
+	bitmap_set(chip->parameters.get_feature_list,
+		   ONFI_FEATURE_ADDR_30LFXG18AC_OTP, 1);
+	bitmap_set(chip->parameters.set_feature_list,
+		   ONFI_FEATURE_ADDR_30LFXG18AC_OTP, 1);
+
+	mtd = nand_to_mtd(chip);
+	mtd->_get_fact_prot_info = macronix_30lfxg18ac_get_otp_info;
+	mtd->_read_fact_prot_reg = macronix_30lfxg18ac_read_otp;
+	mtd->_get_user_prot_info = macronix_30lfxg18ac_get_otp_info;
+	mtd->_read_user_prot_reg = macronix_30lfxg18ac_read_otp;
+	mtd->_write_user_prot_reg = macronix_30lfxg18ac_write_otp;
+	mtd->_lock_user_prot_reg = macronix_30lfxg18ac_lock_otp;
+}
+
 static int macronix_nand_init(struct nand_chip *chip)
 {
 	if (nand_is_slc(chip))
@@ -325,6 +536,7 @@  static int macronix_nand_init(struct nand_chip *chip)
 	macronix_nand_onfi_init(chip);
 	macronix_nand_block_protection_support(chip);
 	macronix_nand_deep_power_down_support(chip);
+	macronix_nand_setup_otp(chip);
 
 	return 0;
 }