mtd: cfi: cmdset_0001: Workaround Micron Erase suspend bug.

commit 46a16a2283f9e678a4e26829175e0c37a5191860 upstream.

Some Micron chips does not work well wrt Erase suspend for
boot blocks. This avoids the issue by not allowing Erase suspend
for the boot blocks for the 28F00AP30(1GBit) chip.

Signed-off-by: Joakim Tjernlund <joakim.tjernlund@infinera.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c
index a239ed4..e1b603c 100644
--- a/drivers/mtd/chips/cfi_cmdset_0001.c
+++ b/drivers/mtd/chips/cfi_cmdset_0001.c
@@ -45,6 +45,7 @@
 #define I82802AB	0x00ad
 #define I82802AC	0x00ac
 #define PF38F4476	0x881c
+#define M28F00AP30	0x8963
 /* STMicroelectronics chips */
 #define M50LPW080       0x002F
 #define M50FLW080A	0x0080
@@ -375,6 +376,17 @@
 		extp->MinorVersion = '1';
 }
 
+static int cfi_is_micron_28F00AP30(struct cfi_private *cfi, struct flchip *chip)
+{
+	/*
+	 * Micron(was Numonyx) 1Gbit bottom boot are buggy w.r.t
+	 * Erase Supend for their small Erase Blocks(0x8000)
+	 */
+	if (cfi->mfr == CFI_MFR_INTEL && cfi->id == M28F00AP30)
+		return 1;
+	return 0;
+}
+
 static inline struct cfi_pri_intelext *
 read_pri_intelext(struct map_info *map, __u16 adr)
 {
@@ -836,6 +848,11 @@
 		    chip->in_progress_block_addr)
 			goto sleep;
 
+		/* do not suspend small EBs, buggy Micron Chips */
+		if (cfi_is_micron_28F00AP30(cfi, chip) &&
+		    (chip->in_progress_block_mask == ~(0x8000-1)))
+			goto sleep;
+
 		/* Erase suspend */
 		map_write(map, CMD(0xB0), chip->in_progress_block_addr);