From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:52535) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h1sgY-000529-Dr for qemu-devel@nongnu.org; Thu, 07 Mar 2019 08:03:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1h1sgS-0003d8-MT for qemu-devel@nongnu.org; Thu, 07 Mar 2019 08:03:42 -0500 From: Markus Armbruster Date: Thu, 7 Mar 2019 14:03:12 +0100 Message-Id: <20190307130323.9353-4-armbru@redhat.com> In-Reply-To: <20190307130323.9353-1-armbru@redhat.com> References: <20190307130323.9353-1-armbru@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v3 03/14] pflash_cfi01: Log use of flawed "write to buffer" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: alex.bennee@linaro.org, lersek@redhat.com, kwolf@redhat.com, mreitz@redhat.com, qemu-block@nongnu.org, qemu-ppc@nongnu.org, philmd@redhat.com, balaton@eik.bme.hu 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-Daud=C3=A9 Reviewed-by: Alex Benn=C3=A9e --- 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 e6d933a06d..d381f14e3c 100644 --- a/hw/block/pflash_cfi01.c +++ b/hw/block/pflash_cfi01.c @@ -502,6 +502,10 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr of= fset, 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 |=3D 0x80; /* Ready! */ break; case 0xf0: /* Probe for AMD flash */ @@ -545,6 +549,7 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr off= set, /* Mask writeblock size based on device width, or bank width= if * device width not specified. */ + /* FIXME check @offset, @width */ if (pfl->device_width) { value =3D extract32(value, 0, pfl->device_width * 8); } else { @@ -582,7 +587,13 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr of= fset, 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 |=3D 0x10; /* Programming error */ @@ -598,6 +609,7 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr off= set, pfl->wcycle++; if (!pfl->ro) { /* Flush the entire write buffer onto backing storag= e. */ + /* FIXME premature! */ pflash_update(pfl, offset & mask, pfl->writeblock_si= ze); } else { pfl->status |=3D 0x10; /* Programming error */ @@ -614,6 +626,7 @@ static void pflash_write(PFlashCFI01 *pfl, hwaddr off= set, switch (pfl->cmd) { case 0xe8: /* Block write */ if (cmd =3D=3D 0xd0) { + /* FIXME this is where we should write out the buffer */ pfl->wcycle =3D 0; pfl->status |=3D 0x80; } else { --=20 2.17.2