[8/8] spi: wpcm-fiu: Add direct map support
Commit Message
Besides software controlled SPI transfers (UMA, "user mode access"), FIU
also supports a 16 MiB mapping window per attached flash chip.
This patch implements direct mapped read access, to speed up flash reads.
Without direct mapping:
# time dd if=/dev/mtd0ro of=dump bs=1M
16+0 records in
16+0 records out
real 1m 47.74s
user 0m 0.00s
sys 1m 47.75s
With direct mapping:
# time dd if=/dev/mtd0ro of=dump bs=1M
16+0 records in
16+0 records out
real 0m 30.81s
user 0m 0.00s
sys 0m 30.81s
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
drivers/spi/spi-wpcm-fiu.c | 64 ++++++++++++++++++++++++++++++++++++++
1 file changed, 64 insertions(+)
--
2.35.1
Comments
Hi Jonathan,
I love your patch! Yet something to improve:
[auto build test ERROR on next-20221104]
[cannot apply to broonie-spi/for-next linusw-pinctrl/devel robh/for-next v6.1-rc3 v6.1-rc2 v6.1-rc1 linus/master v6.1-rc3]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Jonathan-Neusch-fer/Nuvoton-WPCM450-FIU-SPI-flash-controller/20221106-030021
patch link: https://lore.kernel.org/r/20221105185911.1547847-9-j.neuschaefer%40gmx.net
patch subject: [PATCH 8/8] spi: wpcm-fiu: Add direct map support
config: alpha-allyesconfig
compiler: alpha-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/8f83cce55d2b39c9b8934c262a8d01eeebfc5ccc
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Jonathan-Neusch-fer/Nuvoton-WPCM450-FIU-SPI-flash-controller/20221106-030021
git checkout 8f83cce55d2b39c9b8934c262a8d01eeebfc5ccc
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=alpha SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
>> drivers/spi/spi-wpcm-fiu.c:424:24: error: initialization of 'ssize_t (*)(struct spi_mem_dirmap_desc *, u64, size_t, void *)' {aka 'long int (*)(struct spi_mem_dirmap_desc *, long long unsigned int, long unsigned int, void *)'} from incompatible pointer type 'int (*)(struct spi_mem_dirmap_desc *, u64, size_t, void *)' {aka 'int (*)(struct spi_mem_dirmap_desc *, long long unsigned int, long unsigned int, void *)'} [-Werror=incompatible-pointer-types]
424 | .dirmap_read = wpcm_fiu_direct_read,
| ^~~~~~~~~~~~~~~~~~~~
drivers/spi/spi-wpcm-fiu.c:424:24: note: (near initialization for 'wpcm_fiu_mem_ops.dirmap_read')
cc1: some warnings being treated as errors
vim +424 drivers/spi/spi-wpcm-fiu.c
418
419 static const struct spi_controller_mem_ops wpcm_fiu_mem_ops = {
420 .adjust_op_size = wpcm_fiu_adjust_op_size,
421 .supports_op = wpcm_fiu_supports_op,
422 .exec_op = wpcm_fiu_exec_op,
423 .dirmap_create = wpcm_fiu_dirmap_create,
> 424 .dirmap_read = wpcm_fiu_direct_read,
425 };
426
On Sun, Nov 06, 2022 at 05:35:24AM +0800, kernel test robot wrote:
> >> drivers/spi/spi-wpcm-fiu.c:424:24: error: initialization of 'ssize_t (*)(struct spi_mem_dirmap_desc *, u64, size_t, void *)' {aka 'long int (*)(struct spi_mem_dirmap_desc *, long long unsigned int, long unsigned int, void *)'} from incompatible pointer type 'int (*)(struct spi_mem_dirmap_desc *, u64, size_t, void *)' {aka 'int (*)(struct spi_mem_dirmap_desc *, long long unsigned int, long unsigned int, void *)'} [-Werror=incompatible-pointer-types]
> 424 | .dirmap_read = wpcm_fiu_direct_read,
> | ^~~~~~~~~~~~~~~~~~~~
> drivers/spi/spi-wpcm-fiu.c:424:24: note: (near initialization for 'wpcm_fiu_mem_ops.dirmap_read')
> cc1: some warnings being treated as errors
Indeed. I'll fix it.
@@ -51,10 +51,16 @@
*/
#define UMA_WAIT_ITERATIONS 100
+/* The memory-mapped view of flash is 16 MiB long */
+#define MAX_MEMORY_SIZE_PER_CS (16 << 20)
+#define MAX_MEMORY_SIZE_TOTAL (4 * MAX_MEMORY_SIZE_PER_CS)
+
struct wpcm_fiu_spi {
struct device *dev;
struct clk *clk;
void __iomem *regs;
+ void __iomem *memory;
+ size_t memory_size;
struct regmap *shm_regmap;
};
@@ -367,14 +373,64 @@ static int wpcm_fiu_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
return 0;
}
+static int wpcm_fiu_dirmap_create(struct spi_mem_dirmap_desc *desc)
+{
+ struct wpcm_fiu_spi *fiu = spi_controller_get_devdata(desc->mem->spi->controller);
+ int cs = desc->mem->spi->chip_select;
+
+ if (desc->info.op_tmpl.data.dir != SPI_MEM_DATA_IN)
+ return -ENOTSUPP;
+
+ /*
+ * Unfortunately, FIU only supports a 16 MiB direct mapping window (per
+ * attached flash chip), but the SPI MEM core doesn't support partial
+ * direct mappings. This means that we can't support direct mapping on
+ * flashes that are bigger than 16 MiB.
+ */
+ if (desc->info.offset + desc->info.length > MAX_MEMORY_SIZE_PER_CS)
+ return -ENOTSUPP;
+
+ /* Don't read past the memory window */
+ if (cs * MAX_MEMORY_SIZE_PER_CS + desc->info.offset + desc->info.length > fiu->memory_size)
+ return -ENOTSUPP;
+
+ return 0;
+}
+
+static int wpcm_fiu_direct_read(struct spi_mem_dirmap_desc *desc, u64 offs, size_t len, void *buf)
+{
+ struct wpcm_fiu_spi *fiu = spi_controller_get_devdata(desc->mem->spi->controller);
+ int cs = desc->mem->spi->chip_select;
+
+ if (offs >= MAX_MEMORY_SIZE_PER_CS)
+ return -ENOTSUPP;
+
+ offs += cs * MAX_MEMORY_SIZE_PER_CS;
+
+ if (!fiu->memory || offs >= fiu->memory_size)
+ return -ENOTSUPP;
+
+ len = min_t(size_t, len, fiu->memory_size - offs);
+ memcpy_fromio(buf, fiu->memory + offs, len);
+
+ return len;
+}
+
static const struct spi_controller_mem_ops wpcm_fiu_mem_ops = {
.adjust_op_size = wpcm_fiu_adjust_op_size,
.supports_op = wpcm_fiu_supports_op,
.exec_op = wpcm_fiu_exec_op,
+ .dirmap_create = wpcm_fiu_dirmap_create,
+ .dirmap_read = wpcm_fiu_direct_read,
};
static void wpcm_fiu_hw_init(struct wpcm_fiu_spi *fiu)
{
+ /* Configure memory-mapped flash access */
+ writeb(FIU_BURST_CFG_R16, fiu->regs + FIU_BURST_BFG);
+ writeb(MAX_MEMORY_SIZE_TOTAL / (512 << 10), fiu->regs + FIU_CFG);
+ writeb(MAX_MEMORY_SIZE_PER_CS / (512 << 10) | BIT(6), fiu->regs + FIU_SPI_FL_CFG);
+
/* Deassert all manually asserted chip selects */
writeb(0x0f, fiu->regs + FIU_UMA_ECTS);
}
@@ -404,6 +460,14 @@ static int wpcm_fiu_probe(struct platform_device *pdev)
if (IS_ERR(fiu->clk))
return PTR_ERR(fiu->clk);
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "memory");
+ fiu->memory = devm_ioremap_resource(dev, res);
+ fiu->memory_size = min_t(size_t, resource_size(res), MAX_MEMORY_SIZE_TOTAL);
+ if (IS_ERR(fiu->regs)) {
+ dev_err(dev, "Failed to map flash memory window\n");
+ return PTR_ERR(fiu->memory);
+ }
+
fiu->shm_regmap = syscon_regmap_lookup_by_phandle_optional(dev->of_node, "nuvoton,shm");
wpcm_fiu_hw_init(fiu);