From 46fb7809b5520e2cb77bdc86270b0c393e4b1210 Mon Sep 17 00:00:00 2001 From: Stephen Checkoway Date: Fri, 26 Apr 2019 12:26:20 -0400 Subject: hw/block/pflash_cfi02: Fix CFI in autoselect mode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit After a flash device enters CFI mode from autoselect mode, the reset command returns the device to autoselect mode. An additional reset command is necessary to return to read array mode. Signed-off-by: Stephen Checkoway Message-Id: <20190426162624.55977-7-stephen.checkoway@oberlin.edu> Tested-by: Philippe Mathieu-Daudé Acked-by: Thomas Huth Acked-by: Alistair Francis Acked-by: Philippe Mathieu-Daudé Signed-off-by: Philippe Mathieu-Daudé --- hw/block/pflash_cfi02.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) (limited to 'hw/block') diff --git a/hw/block/pflash_cfi02.c b/hw/block/pflash_cfi02.c index 08b2bc8..13f76fa 100644 --- a/hw/block/pflash_cfi02.c +++ b/hw/block/pflash_cfi02.c @@ -66,6 +66,7 @@ do { \ /* Special write cycles for CFI queries. */ enum { WCYCLE_CFI = 7, + WCYCLE_AUTOSELECT_CFI = 8, }; struct PFlashCFI02 { @@ -311,6 +312,12 @@ static void pflash_write(void *opaque, hwaddr offset, uint64_t value, cmd = value; if (pfl->cmd != 0xA0) { if (cmd == 0xF0) { + if (pfl->wcycle == WCYCLE_AUTOSELECT_CFI) { + /* Return to autoselect mode. */ + pfl->wcycle = 3; + pfl->cmd = 0x90; + return; + } goto reset_flash; } } @@ -333,7 +340,6 @@ static void pflash_write(void *opaque, hwaddr offset, uint64_t value, /* We're in read mode */ check_unlock0: if (boff == 0x55 && cmd == 0x98) { - enter_CFI_mode: /* Enter CFI query mode */ pfl->wcycle = WCYCLE_CFI; pfl->cmd = 0x98; @@ -410,9 +416,16 @@ static void pflash_write(void *opaque, hwaddr offset, uint64_t value, /* Unlock bypass reset */ goto reset_flash; } - /* We can enter CFI query mode from autoselect mode */ - if (boff == 0x55 && cmd == 0x98) - goto enter_CFI_mode; + /* + * We can enter CFI query mode from autoselect mode, but we must + * return to autoselect mode after a reset. + */ + if (boff == 0x55 && cmd == 0x98) { + /* Enter autoselect CFI query mode */ + pfl->wcycle = WCYCLE_AUTOSELECT_CFI; + pfl->cmd = 0x98; + return; + } /* No break here */ default: DPRINTF("%s: invalid write for command %02x\n", @@ -493,6 +506,7 @@ static void pflash_write(void *opaque, hwaddr offset, uint64_t value, break; /* Special values for CFI queries */ case WCYCLE_CFI: + case WCYCLE_AUTOSELECT_CFI: DPRINTF("%s: invalid write in CFI query mode\n", __func__); goto reset_flash; default: -- cgit v1.1