This driver explains too much about what is apparent from the code.
Comments around basic APIs such as init_completion(), spin_lock_init(),
etc. seem unneeded lessons to kernel developers.
(With those comments dropped, denali_drv_init() is small enough,
so it has been merged into the probe function.)
Also, NAND driver developers should know the NAND init procedure, so
there is no need to explain nand_scan_ident/tail.
I removed FSF's address from the license blocks, and added simple
comments to struct members.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Include necessary headers explicitly without relying on indirect
header inclusion. Also, sort them alphabetically.
<linux/delay.h>, <linux/wait.h>, <linux/mutex.h> turned out bogus,
so removed.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Introduce some macros and helpers to avoid magic numbers and
rename macros/functions for clarification.
- We see '| 2' in several places. This means Data Cycle in MAP11 mode.
The Denali User's Guide says bit[1:0] of MAP11 is like follows:
b'00 = Command Cycle
b'01 = Address Cycle
b'10 = Data Cycle
So, this commit added DENALI_MAP11_{CMD,ADDR,DATA} macros.
- We see 'denali->flash_mem + 0x10' in several places, but 0x10 is a
magic number. Actually, this accesses the data port of the Host
Data/Command Interface. So, this commit added DENALI_HOST_DATA.
On the other hand, 'denali->flash_mem' gets access to the address
port, so DENALI_HOST_ADDR was also added.
- We see 'index_addr(denali, cmd, 0x1)' in denali_erase(), but 0x1
is a magic number. 0x1 means the erase operation. Replace 0x1
with DENALI_ERASE.
- Rename index_addr() to denali_host_write() for clarification
- Denali User's Guide says MAP{00,01,10,11} for access mode. Match
the macros with terminology in the IP document.
- Rename struct members as follows:
flash_bank -> active_bank (currently selected bank)
flash_reg -> reg (base address of registers)
flash_mem -> host (base address of host interface)
devnum -> devs_per_cs (devices connected in parallel)
bbtskipbytes -> oob_skip_bytes (number of bytes to skip in OOB)
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Handling timing parameters in a driver's own way should be avoided
because it duplicates efforts of drivers/mtd/nand/nand_timings.c
Besides, this driver hard-codes Intel specific parameters such as
CLK_X=5, CLK_MULTI=4. Taking a certain device (Samsung K9WAG08U1A)
into account by get_samsung_nand_para() is weird as well.
Now, the core framework provides .setup_data_interface() hook, which
handles timing parameters in a generic manner.
While I am working on this, I found even more issues in the current
code, so fixed the following as well:
- In recent IP versions, WE_2_RE and TWHR2 share the same register.
Likewise for ADDR_2_DATA and TCWAW, CS_SETUP_CNT and TWB. When
updating one, the other must be masked. Otherwise, the other will
be set to 0, then timing settings will be broken.
- The recent IP release expanded the ADDR_2_DATA to 7-bit wide.
This register is related to tADL. As commit 74a332e78e ("mtd:
nand: timings: Fix tADL_min for ONFI 4.0 chips") addressed, the
ONFi 4.0 increased the minimum of tADL to 400 nsec. This may not
fit in the 6-bit ADDR_2_DATA in older versions. Check the IP
revision and handle this correctly, otherwise the register value
would wrap around.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
This driver was originally written for the Intel MRST platform with
several platform-specific parameters hard-coded.
Currently, the ECC settings are hard-coded as follows:
#define ECC_SECTOR_SIZE 512
#define ECC_8BITS 14
#define ECC_15BITS 26
Therefore, the driver can only support two cases.
- ecc.size = 512, ecc.strength = 8 --> ecc.bytes = 14
- ecc.size = 512, ecc.strength = 15 --> ecc.bytes = 26
However, these are actually customizable parameters, for example,
UniPhier platform supports the following:
- ecc.size = 1024, ecc.strength = 8 --> ecc.bytes = 14
- ecc.size = 1024, ecc.strength = 16 --> ecc.bytes = 28
- ecc.size = 1024, ecc.strength = 24 --> ecc.bytes = 42
So, we need to handle the ECC parameters in a more generic manner.
Fortunately, the Denali User's Guide explains how to calculate the
ecc.bytes. The formula is:
ecc.bytes = 2 * CEIL(13 * ecc.strength / 16) (for ecc.size = 512)
ecc.bytes = 2 * CEIL(14 * ecc.strength / 16) (for ecc.size = 1024)
For DT platforms, it would be reasonable to allow DT to specify ECC
strength by either "nand-ecc-strength" or "nand-ecc-maximize". If
none of them is specified, the driver will try to meet the chip's ECC
requirement.
For PCI platforms, the max ECC strength is used to keep the original
behavior.
Newer versions of this IP need ecc.size and ecc.steps explicitly
set up via the following registers:
CFG_DATA_BLOCK_SIZE (0x6b0)
CFG_LAST_DATA_BLOCK_SIZE (0x6c0)
CFG_NUM_DATA_BLOCKS (0x6d0)
For older IP versions, write accesses to these registers are just
ignored.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
The driver calls devm_kzalloc()/devm_kfree() to allocate/free memory.
They are declared in <linux/device.h>, not in <linux/slab.h>.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
It is better to have device name prefixed the actual error message.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
In recent kernels we have a lot of helper functions, including
devres API, to make life of device driver developer easy.
Convert the driver using devm_kzalloc() and pcim_enable_device().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Let's use module_pci_driver() macro to reduce code base of the driver.
There is no functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
The kernel already has this information, and individual drivers
shouldn't duplicate that. This also eliminates the use of __DATE__ and
__TIME__, which make the build non-deterministic.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Don't use DEFINE_PCI_DEVICE_TABLE macro, because this macro
is not preferred.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
The Denali controller can also be found in SoC devices attached to a
simple bus. Move the PCI specific parts into denali_pci so that we can
add a denali_dt that uses the same driver but for a device tree driver
instead of a PCI based device.
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Masahiro Yamada