Commit Graph

6 Commits

Author SHA1 Message Date
Glenn Miles
4d2cd2d869 ppc/pnv: Test pnv i2c master and connected devices
Tests the following for both P9 and P10:
  - I2C master POR status
  - I2C master status after immediate reset

Tests the following for powernv10-ranier only:
  - Config pca9552 hotplug device pins as inputs then
    Read the INPUT0/1 registers to verify all pins are high
  - Connected GPIO pin tests of P10 PCA9552 device.  Tests
    output of pins 0-4 affect input of pins 5-9 respectively.
  - PCA9554 GPIO pins test.  Tests input and ouput functionality.

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
2024-02-23 23:24:42 +10:00
Glenn Miles
7b85f008b6 ppc/pnv: Use resettable interface to reset child I2C buses
The QEMU I2C buses and devices use the resettable
interface for resetting while the PNV I2C controller
and parent buses and devices have not yet transitioned
to this new interface and use the old reset strategy.
This was preventing the I2C buses and devices wired
to the PNV I2C controller from being reset.

The short term fix for this is to have the PNV I2C
Controller's reset function explicitly call the resettable
interface function, bus_cold_reset(), on all child
I2C buses.

The long term fix should be to transition all PNV parent
devices and buses to use the resettable interface so that
all child buses and devices are automatically reset.

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
2024-02-23 23:24:42 +10:00
Glenn Miles
b664466d8f ppc/pnv: Fix PNV I2C invalid status after reset
The PNV I2C Controller was clearing the status register
after a reset without repopulating the "upper threshold
for I2C ports", "Command Complete" and the SCL/SDA input
level fields.

Fixed this for resets caused by a system reset as well
as from writing to the "Immediate Reset" register.

Fixes: 263b81ee15 ("ppc/pnv: Add an I2C controller model")
Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2023-11-21 08:39:58 +01:00
Glenn Miles
47dfdd238d ppc/pnv: PNV I2C engines assigned incorrect XSCOM addresses
The PNV I2C engines for power9 and power10 were being assigned a base
XSCOM address that was off by one I2C engine's address range such
that engine 0 had engine 1's address and so on.  The xscom address
assignment was being based on the device tree engine numbering, which
starts at 1.  Rather than changing the device tree numbering to start
with 0, the addressing was changed to be based on the existing device
tree numbers minus one.

Fixes: 1ceda19c28 ("ppc/pnv: Connect PNV I2C controller to powernv10)
Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2023-11-21 08:39:58 +01:00
Cédric Le Goater
8bc5ae046d ppc/pnv: Fix potential overflow in I2C model
Coverity warns that "i2c_bus_busy(i2c->busses[i]) << i" might overflow
because the expression is evaluated using 32-bit arithmetic and then
used in a context expecting a uint64_t.

While we are at it, introduce a PNV_I2C_MAX_BUSSES constant and check
the number of busses at realize time.

Fixes: Coverity CID 1523918
Cc: Glenn Miles <milesg@linux.vnet.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2023-11-21 08:39:57 +01:00
Cédric Le Goater
263b81ee15 ppc/pnv: Add an I2C controller model
The more recent IBM power processors have an embedded I2C
controller that is accessible by software via the XSCOM
address space.

Each instance of the I2C controller is capable of controlling
multiple I2C buses (one at a time).  Prior to beginning a
transaction on an I2C bus, the bus must be selected by writing
the port number associated with the bus into the PORT_NUM
field of the MODE register.  Once an I2C bus is selected,
the status of the bus can be determined by reading the
Status and Extended Status registers.

I2C bus transactions can be started by writing a command to
the Command register and reading/writing data from/to the
FIFO register.

Not supported :

 . 10 bit I2C addresses
 . Multimaster
 . Slave

Signed-off-by: Cédric Le Goater <clg@kaod.org>
[milesg: Split wiring to powernv9 into its own commit]
[milesg: Added more detail to commit message]
[milesg: Added SPDX Licensed Identifier to new files]
[milesg: updated copyright dates]
[milesg: Added use of g_autofree]
[milesg: Added NULL check after pnv_i2c_get_bus]
Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Acked-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-ID: <20231016222013.3739530-2-milesg@linux.vnet.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2023-11-07 15:49:41 -03:00