| Message ID | 1386339891-32717-8-git-send-email-sourav.poddar@ti.com |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Dec 06, 2013 at 07:54:48PM +0530, Sourav Poddar wrote: > Adapt driver to do a memory mapped read. > @@ -109,6 +109,7 @@ struct m25p { > u8 program_opcode; > u8 *command; > enum read_type flash_read; > + void __iomem *mem_addr; I think we can remove this field. You can use a local variable in the m25p80_read. > }; > > static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd) > @@ -515,6 +516,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, > size_t *retlen, u_char *buf) > { > struct m25p *flash = mtd_to_m25p(mtd); > + struct spi_master *master = flash->spi->master; > struct spi_transfer t[2]; > struct spi_message m; > uint8_t opcode; > @@ -523,6 +525,20 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, > pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev), > __func__, (u32)from, len); > > + if (master->mmap) { > + mutex_lock(&flash->lock); > + /* Wait till previous write/erase is done. */ > + if (wait_till_ready(flash)) { > + mutex_unlock(&flash->lock); > + return 1; > + } > + flash->mem_addr = master->get_buf(master); > + memcpy(buf, flash->mem_addr + from, len); > + master->put_buf(master); > + *retlen = len; > + goto out; > + } > + > spi_message_init(&m); > memset(t, 0, (sizeof t)); > > @@ -558,6 +574,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, > > *retlen = m.actual_length - m25p_cmdsz(flash) - dummy; > > +out: > mutex_unlock(&flash->lock); > > return 0; > @@ -1286,6 +1303,9 @@ static int m25p_probe(struct spi_device *spi) > flash->addr_width = 3; > } > > + if (spi->master->configure_from_slave) > + m25p80_fill_flash_information(flash); > + You have add a configure_from_slave hook in the SPI, why you also need a same hook in the SPI-NOR framework? And i think the enable_mmap/disable_mmap is not needed too. All the three hooks are used to set the SPI bus controller. And the SPI-NOR framework only handles the issues between the SPI bus controller and the SPI-NOR, or the SPI-NOR controller and the SPI-NOR. thanks Huang Shijie
On Thursday 12 December 2013 01:25 PM, Huang Shijie wrote: > On Fri, Dec 06, 2013 at 07:54:48PM +0530, Sourav Poddar wrote: >> Adapt driver to do a memory mapped read. >> @@ -109,6 +109,7 @@ struct m25p { >> u8 program_opcode; >> u8 *command; >> enum read_type flash_read; >> + void __iomem *mem_addr; > I think we can remove this field. > You can use a local variable in the m25p80_read. > >> }; >> >> static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd) >> @@ -515,6 +516,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, >> size_t *retlen, u_char *buf) >> { >> struct m25p *flash = mtd_to_m25p(mtd); >> + struct spi_master *master = flash->spi->master; >> struct spi_transfer t[2]; >> struct spi_message m; >> uint8_t opcode; >> @@ -523,6 +525,20 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, >> pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev), >> __func__, (u32)from, len); >> >> + if (master->mmap) { >> + mutex_lock(&flash->lock); >> + /* Wait till previous write/erase is done. */ >> + if (wait_till_ready(flash)) { >> + mutex_unlock(&flash->lock); >> + return 1; >> + } >> + flash->mem_addr = master->get_buf(master); >> + memcpy(buf, flash->mem_addr + from, len); >> + master->put_buf(master); >> + *retlen = len; >> + goto out; >> + } >> + >> spi_message_init(&m); >> memset(t, 0, (sizeof t)); >> >> @@ -558,6 +574,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, >> >> *retlen = m.actual_length - m25p_cmdsz(flash) - dummy; >> >> +out: >> mutex_unlock(&flash->lock); >> >> return 0; >> @@ -1286,6 +1303,9 @@ static int m25p_probe(struct spi_device *spi) >> flash->addr_width = 3; >> } >> >> + if (spi->master->configure_from_slave) >> + m25p80_fill_flash_information(flash); >> + > You have add a configure_from_slave hook in the SPI, why you also need > a same hook in the SPI-NOR framework? > We need a way to provoke this, currently it is placed in m25p80. If m25p80 is removed, for where should I handle these in nor framework? > And i think the enable_mmap/disable_mmap is not needed too. > > All the three hooks are used to set the SPI bus controller. > And the SPI-NOR framework only handles the issues between the > SPI bus controller and the SPI-NOR, or the SPI-NOR controller and the > SPI-NOR. My controller can be used as spi flash controller as well as a spi controller. > thanks > Huang Shijie > >
On Thu, Dec 12, 2013 at 01:45:24PM +0530, Sourav Poddar wrote: > On Thursday 12 December 2013 01:25 PM, Huang Shijie wrote: > >> > >>+ if (spi->master->configure_from_slave) > >>+ m25p80_fill_flash_information(flash); > >>+ > >You have add a configure_from_slave hook in the SPI, why you also need > >a same hook in the SPI-NOR framework? > > > We need a way to provoke this, currently it is placed in m25p80. If m25p80 > is removed, for where should I handle these in nor framework? The m25p80 is not removed. it is easy to move your code in the m25p_read. Please read the patch 4. > >And i think the enable_mmap/disable_mmap is not needed too. > > > >All the three hooks are used to set the SPI bus controller. > > >And the SPI-NOR framework only handles the issues between the > >SPI bus controller and the SPI-NOR, or the SPI-NOR controller and the > >SPI-NOR. > My controller can be used as spi flash controller as well as a spi > controller. > If you really think we need to do something before the do the real work. we can add two hooks : prepare/unprepare. for you, you can put the the enable_mmap/disable_mmap in the prepare/unprepare separately. for other driver, we can put the enable/disable clocks in the prepare/unprepare hooks. thanks Huang Shijie
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index b90c7e5..eb75d84 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -109,6 +109,7 @@ struct m25p { u8 program_opcode; u8 *command; enum read_type flash_read; + void __iomem *mem_addr; }; static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd) @@ -515,6 +516,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf) { struct m25p *flash = mtd_to_m25p(mtd); + struct spi_master *master = flash->spi->master; struct spi_transfer t[2]; struct spi_message m; uint8_t opcode; @@ -523,6 +525,20 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev), __func__, (u32)from, len); + if (master->mmap) { + mutex_lock(&flash->lock); + /* Wait till previous write/erase is done. */ + if (wait_till_ready(flash)) { + mutex_unlock(&flash->lock); + return 1; + } + flash->mem_addr = master->get_buf(master); + memcpy(buf, flash->mem_addr + from, len); + master->put_buf(master); + *retlen = len; + goto out; + } + spi_message_init(&m); memset(t, 0, (sizeof t)); @@ -558,6 +574,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, *retlen = m.actual_length - m25p_cmdsz(flash) - dummy; +out: mutex_unlock(&flash->lock); return 0; @@ -1286,6 +1303,9 @@ static int m25p_probe(struct spi_device *spi) flash->addr_width = 3; } + if (spi->master->configure_from_slave) + m25p80_fill_flash_information(flash); + dev_info(&spi->dev, "%s (%lld Kbytes)\n", id->name, (long long)flash->mtd.size >> 10);
Adapt driver to do a memory mapped read. Signed-off-by: Sourav Poddar <sourav.poddar@ti.com> --- v1->v2: - Add a check to Wait for the previous erase/write to finish. - Ensure proper locking drivers/mtd/devices/m25p80.c | 20 ++++++++++++++++++++ 1 files changed, 20 insertions(+), 0 deletions(-)