[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH 14/25] hw/nvram/eeprom_at24c: Make reset behavior more like hardw
From: |
Cédric Le Goater |
Subject: |
[PATCH 14/25] hw/nvram/eeprom_at24c: Make reset behavior more like hardware |
Date: |
Thu, 19 Jan 2023 13:34:38 +0100 |
From: Peter Delevoryas <peter@pjd.dev>
EEPROM's are a form of non-volatile memory. After power-cycling an EEPROM,
I would expect the I2C state machine to be reset to default values, but I
wouldn't really expect the memory to change at all.
The current implementation of the at24c EEPROM resets its internal memory on
reset. This matches the specification in docs/devel/reset.rst:
Cold reset is supported by every resettable object. In QEMU, it means we reset
to the initial state corresponding to the start of QEMU; this might differ
from what is a real hardware cold reset. It differs from other resets (like
warm or bus resets) which may keep certain parts untouched.
But differs from my intuition. For example, if someone writes some information
to an EEPROM, then AC power cycles their board, they would expect the EEPROM to
retain that information. It's very useful to be able to test things like this
in QEMU as well, to verify software instrumentation like determining the cause
of a reboot.
Fixes: 5d8424dbd3e8 ("nvram: add AT24Cx i2c eeprom")
Signed-off-by: Peter Delevoryas <peter@pjd.dev>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
hw/nvram/eeprom_at24c.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/hw/nvram/eeprom_at24c.c b/hw/nvram/eeprom_at24c.c
index f8d751fa27..5074776bff 100644
--- a/hw/nvram/eeprom_at24c.c
+++ b/hw/nvram/eeprom_at24c.c
@@ -185,18 +185,6 @@ static void at24c_eeprom_realize(DeviceState *dev, Error
**errp)
}
ee->mem = g_malloc0(ee->rsize);
-
-}
-
-static
-void at24c_eeprom_reset(DeviceState *state)
-{
- EEPROMState *ee = AT24C_EE(state);
-
- ee->changed = false;
- ee->cur = 0;
- ee->haveaddr = 0;
-
memset(ee->mem, 0, ee->rsize);
if (ee->init_rom) {
@@ -214,6 +202,16 @@ void at24c_eeprom_reset(DeviceState *state)
}
}
+static
+void at24c_eeprom_reset(DeviceState *state)
+{
+ EEPROMState *ee = AT24C_EE(state);
+
+ ee->changed = false;
+ ee->cur = 0;
+ ee->haveaddr = 0;
+}
+
static Property at24c_eeprom_props[] = {
DEFINE_PROP_UINT32("rom-size", EEPROMState, rsize, 0),
DEFINE_PROP_BOOL("writable", EEPROMState, writable, true),
--
2.39.0
- [PATCH 04/25] avocado/boot_linux_console.py: Update ast2600 test, (continued)
- [PATCH 04/25] avocado/boot_linux_console.py: Update ast2600 test, Cédric Le Goater, 2023/01/19
- [PATCH 05/25] m25p80: Add the is25wp256 SFPD table, Cédric Le Goater, 2023/01/19
- [PATCH 06/25] tests/avocado/machine_aspeed.py: update buildroot tests, Cédric Le Goater, 2023/01/19
- [PATCH 07/25] tests/avocado/machine_aspeed.py: Mask systemd services to speed up SDK boot, Cédric Le Goater, 2023/01/19
- [PATCH 08/25] hw/arm/boot: Export write_bootloader for Aspeed machines, Cédric Le Goater, 2023/01/19
- [PATCH 09/25] hw/core/loader: Remove declarations of option_rom_has_mr/rom_file_has_mr, Cédric Le Goater, 2023/01/19
- [PATCH 10/25] hw/arm: Extract at24c_eeprom_init helper from Aspeed and Nuvoton boards, Cédric Le Goater, 2023/01/19
- [PATCH 11/25] hw/arm/aspeed: Replace aspeed_eeprom_init with at24c_eeprom_init, Cédric Le Goater, 2023/01/19
- [PATCH 12/25] hw/nvram/eeprom_at24c: Add init_rom field and at24c_eeprom_init_rom helper, Cédric Le Goater, 2023/01/19
- [PATCH 13/25] hw/arm/aspeed: Add aspeed_eeprom.c, Cédric Le Goater, 2023/01/19
- [PATCH 14/25] hw/nvram/eeprom_at24c: Make reset behavior more like hardware,
Cédric Le Goater <=
- [PATCH 15/25] target/arm: Allow users to set the number of VFP registers, Cédric Le Goater, 2023/01/19
- [PATCH 17/25] hw/watchdog/wdt_aspeed: Extend MMIO range to cover more registers, Cédric Le Goater, 2023/01/19
- [PATCH 18/25] hw/watchdog/wdt_aspeed: Log unimplemented registers as UNIMP level, Cédric Le Goater, 2023/01/19
- [PATCH 20/25] hw/arm/aspeed_ast10x0: Add various unimplemented peripherals, Cédric Le Goater, 2023/01/19
- [PATCH 21/25] hw/arm/aspeed_ast10x0: Map I3C peripheral, Cédric Le Goater, 2023/01/19
- [PATCH 16/25] hw/watchdog/wdt_aspeed: Rename MMIO region size as 'iosize', Cédric Le Goater, 2023/01/19
- [PATCH 24/25] hw/arm/aspeed_ast10x0: Add TODO comment to use Cortex-M4F, Cédric Le Goater, 2023/01/19
- [PATCH 19/25] hw/misc/aspeed_hace: Do not crash if address_space_map() failed, Cédric Le Goater, 2023/01/19