From d35903b0e772c0cdcd3f685dbee81ffbd110a24a Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Fri, 17 May 2019 06:50:54 +0200 Subject: [PATCH 27/53] pflash_cfi01: Log use of flawed "write to buffer" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Markus Armbruster Message-id: <20190517065120.12028-6-armbru@redhat.com> Patchwork-id: 87990 O-Subject: [RHEL-7.7 qemu-kvm-rhev PATCH v3 05/31] pflash_cfi01: Log use of flawed "write to buffer" Bugzilla: 1624009 RH-Acked-by: Philippe Mathieu-Daudé RH-Acked-by: Thomas Huth RH-Acked-by: Miroslav Rezanina Our implementation of "write to buffer" (command 0xE8) is flawed. LOG_UNIMP its use, and add some FIXME comments. Signed-off-by: Markus Armbruster Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Alex Bennée Message-Id: <20190308094610.21210-4-armbru@redhat.com> (cherry picked from commit 4dbda935e054600667f9e57095fa97e2ce5936f9) Signed-off-by: Miroslav Rezanina --- hw/block/pflash_cfi01.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c index c565db1..3a6bd10 100644 --- a/hw/block/pflash_cfi01.c +++ b/hw/block/pflash_cfi01.c @@ -515,6 +515,10 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr offset, break; case 0xe8: /* Write to buffer */ DPRINTF("%s: Write to buffer\n", __func__); + /* FIXME should save @offset, @width for case 1+ */ + qemu_log_mask(LOG_UNIMP, + "%s: Write to buffer emulation is flawed\n", + __func__); pfl->status |= 0x80; /* Ready! */ break; case 0xf0: /* Probe for AMD flash */ @@ -558,6 +562,7 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr offset, /* Mask writeblock size based on device width, or bank width if * device width not specified. */ + /* FIXME check @offset, @width */ if (pfl->device_width) { value = extract32(value, 0, pfl->device_width * 8); } else { @@ -595,7 +600,13 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr offset, case 2: switch (pfl->cmd) { case 0xe8: /* Block write */ + /* FIXME check @offset, @width */ if (!pfl->ro) { + /* + * FIXME writing straight to memory is *wrong*. We + * should write to a buffer, and flush it to memory + * only on confirm command (see below). + */ pflash_data_write(pfl, offset, value, width, be); } else { pfl->status |= 0x10; /* Programming error */ @@ -611,6 +622,7 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr offset, pfl->wcycle++; if (!pfl->ro) { /* Flush the entire write buffer onto backing storage. */ + /* FIXME premature! */ pflash_update(pfl, offset & mask, pfl->writeblock_size); } else { pfl->status |= 0x10; /* Programming error */ @@ -627,6 +639,7 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr offset, switch (pfl->cmd) { case 0xe8: /* Block write */ if (cmd == 0xd0) { + /* FIXME this is where we should write out the buffer */ pfl->wcycle = 0; pfl->status |= 0x80; } else { -- 1.8.3.1