/*
* Freescale GPMI NAND Flash Driver
*
* Copyright (C) 2008-2011 Freescale Semiconductor, Inc.
* Copyright (C) 2008 Embedded Alley Solutions, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/mtd/gpmi-nand.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <mach/mxs.h>
#include "gpmi-nand.h"
#include "gpmi-regs.h"
#include "bch-regs.h"
struct timing_threshod timing_default_threshold = {
.max_data_setup_cycles = (BM_GPMI_TIMING0_DATA_SETUP >>
BP_GPMI_TIMING0_DATA_SETUP),
.internal_data_setup_in_ns = 0,
.max_sample_delay_factor = (BM_GPMI_CTRL1_RDN_DELAY >>
BP_GPMI_CTRL1_RDN_DELAY),
.max_dll_clock_period_in_ns = 32,
.max_dll_delay_in_ns = 16,
};
/*
* Clear the bit and poll it cleared. This is usually called with
* a reset address and mask being either SFTRST(bit 31) or CLKGATE
* (bit 30).
*/
static int clear_poll_bit(void __iomem *addr, u32 mask)
{
int timeout = 0x400;
/* clear the bit */
__mxs_clrl(mask, addr);
/*
* SFTRST needs 3 GPMI clocks to settle, the reference manual
* recommends to wait 1us.
*/
udelay(1);
/* poll the bit becoming clear */
while ((readl(addr) & mask) && --timeout)
/* nothing */;
return !timeout;
}
#define MODULE_CLKGATE (1 << 30)
#define MODULE_SFTRST (1 << 31)
/*
* The current mxs_reset_block() will do two things:
* [1] enable the module.
* [2] reset the module.
*
* In most of the cases, it's ok.
* But in MX23, there is a hardware bug in the BCH block (see erratum #2847).
* If you try to soft reset the BCH block, it becomes unusable until
* the next hard reset. This case occurs in the NAND boot mode. When the board
* boots by NAND, the ROM of the chip will initialize the BCH blocks itself.
* So If the driver tries to reset the BCH again, the BCH will not work anymore.
* You will see a DMA timeout in this case. The bug has been fixed
* in the following chips, such as MX28.
*
* To avoid this bug, just add a new parameter `just_enable` for
* the mxs_reset_block(), and rewrite it here.
*/
static int gpmi_reset_block(void __iomem *reset_addr, bool just_enable)
{
int ret;
int timeout = 0x400;
/* clear and poll SFTRST */
ret = clear_poll_bit(reset_addr, MODULE_SFTRST);
if (unlikely(ret))
goto error;
/* clear CLKGATE */
__mxs_clrl(MODULE_CLKGATE, reset_addr);
if (!just_enable) {
/* set SFTRST to reset the block */
__mxs_setl(MODULE_SFTRST, reset_addr);
udelay(1);
/* poll CLKGATE becoming set */
while ((!(readl(reset_addr) & MODULE_CLKGATE)) && --timeout)
/* nothing */;
if (unlikely(!timeout))
goto error;
}
/* clear and poll SFTRST */
ret = clear_poll_bit(reset_addr, MODULE_SFTRST);
if (unlikely(ret))
goto error;
/* clear and poll CLKGATE */
ret = clear_poll_bit(reset_addr, MODULE_CLKGATE);
if (unlikely(ret))
goto error;
return 0;
error:
pr_err("%s(%p): module reset timeout\n", __func__, reset_addr);
return -ETIMEDOUT;
}
int gpmi_init(struct gpmi_nand_data *this)
{
struct resources *r = &this->resources;
int ret;
ret = clk_prepare_enable(r->clock);
if (ret)
goto err_out;
ret = gpmi_reset_block(r->gpmi_regs, false);
if (ret)
goto err_out;
/* Choose NAND mode. */
writel(BM_GPMI_CTRL1_GPMI_MODE, r->gpmi_regs + HW_GPMI_CTRL1_CLR);
/* Set the IRQ polarity. */
writel(BM_GPMI_CTRL1_ATA_IRQRDY_POLARITY,
r->gpmi_regs + HW_GPMI_CTRL1_SET);
/* Disable Write-Protection. */
writel(BM_GPMI_CTRL1_DEV_RESET, r->gpmi_regs + HW_GPMI_CTRL1_SET);
/* Select BCH ECC. */
writel(BM_GPMI_CTRL1_BCH_MODE, r->gpmi_regs + HW_GPMI_CTRL1_SET);
clk_disable_unprepare(r->clock);
return 0;
err_out:
return ret;
}
/* This function is very useful. It is called only when the bug occur. */
void gpmi_dump_info(struct gpmi_nand_data *this)
{
struct resources *r = &this->resources;
struct bch_geometry *geo = &this->bch_geometry;
u32 reg;
int i;
pr_err("Show GPMI registers :\n");
for (i = 0; i <= HW_GPMI_DEBUG / 0x10 + 1; i++) {
reg = readl(r->gpmi_regs + i * 0x10);
pr_err("offset 0x%.3x : 0x%.8x\n", i * 0x10, reg);
}
/* start to print out the BCH info */
pr_err("BCH Geometry :\n");
pr_err("GF length : %u\n", geo->gf_len);
pr_err("ECC Strength : %u\n", geo->ecc_strength);
pr_err("Page Size in Bytes : %u\n", geo->page_size);
pr_err("Metadata Size in Bytes : %u\n", geo->metadata_size);
pr_err("ECC Chunk Size in Bytes: %u\n", geo->ecc_chunk_size);
pr_err("ECC Chunk Count : %u\n", geo->ecc_chunk_count);
pr_err("Payload Size in Bytes : %u\n", geo->payload_size);
pr_err("Auxiliary Size in Bytes: %u\n", geo->auxiliary_size);
pr_err("Auxiliary Status Offset: %u\n", geo->auxiliary_status_offset);
pr_err("Block Mark Byte Offset : %u\n", geo->block_mark_byte_offset);
pr_err("Block Mark Bit Offset : %u\n", geo->block_mark_bit_offset);
}
/* Configures the geometry for BCH. */
int bch_set_geometry(struct gpmi_nand_data *this)
{
struct resources *r = &this->resources;
struct bch_geometry *bch_geo = &this->bch_geometry;
unsigned int block_count;
unsigned int block_size;
unsigned int metadata_size;
unsigned int ecc_strength;
unsigned int page_size;
int ret;
if (common_nfc_set_geometry(this))
return !0;
block_count = bch_geo->ecc_chunk_count - 1;
block_size = bch_geo->ecc_chunk_size;
metadata_size = bch_geo->metadata_size;
ecc_strength = bch_geo->ecc_strength >> 1;
page_size = bch_geo->page_size;
ret = clk_prepare_enable(r->clock);
if (ret)
goto err_out;
/*
* Due to erratum #2847 of the MX23, the BCH cannot be soft reset on this
* chip, otherwise it will lock up. So we skip resetting BCH on the MX23.
* On the other hand, the MX28 needs the reset, because one case has been
* seen where the BCH produced ECC errors constantly after 10000
* consecutive reboots. The latter case has not been seen on the MX23 yet,
* still we don't know if it could happen there as well.
*/
ret = gpmi_reset_block(r->bch_regs, GPMI_IS_MX23(this));
if (ret)
goto err_out;
/* Configure layout 0. */
writel(BF_BCH_FLASH0LAYOUT0_NBLOCKS(block_count)
| BF_BCH_FLASH0LAYOUT0_META_SIZE(metadata_size)
| BF_BCH_FLASH0LAYOUT0_ECC0(ecc_strength)
| BF_BCH_FLASH0LAYOUT0_DATA0_SIZE(block_size),
r->bch_regs + HW_BCH_FLASH0LAYOUT0);
writel(BF_BCH_FLASH0LAYOUT1_PAGE_SIZE(page_size)
| BF_BCH_FLASH0LAYOUT1_ECCN(ecc_strength)
| BF_BCH_FLASH0LAYOUT1_DATAN_SIZE(block_size),
r->bch_regs + HW_BCH_FLASH0LAYOUT1);
/* Set *all* chip selects to use layout 0. */
writel(0, r->bch_regs + HW_BCH_LAYOUTSELECT);
/* Enable interrupts. */
writel(BM_BCH_CTRL_COMPLETE_IRQ_EN,
r->bch_regs + HW_BCH_CTRL_SET);
clk_disable_unprepare(r->clock);
return 0;
err_out:
return ret;
}
/* Converts time in nanoseconds to cycles. */
static unsigned int ns_to_cycles(unsigned int time,
unsigned int period, unsigned int min)
{
unsigned int k;
k = (time + period - 1) / period;
return max(k, min);
}
/* Apply timing to current hardware conditions. */
static int gpmi_nfc_compute_hardware_timing(struct gpmi_nand_data *this,
struct gpmi_nfc_hardware_timing *hw)
{
struct gpmi_nand_platform_data *pdata = this->pdata;
struct timing_threshod *nfc = &timing_default_threshold;
struct nand_chip *nand = &this->nand;
struct nand_timing target = this->timing;
bool improved_timing_is_available;
unsigned long clock_frequency_in_hz;
unsigned int clock_period_in_ns;
bool dll_use_half_periods;
unsigned int dll_delay_shift;
unsigned int max_sample_delay_in_ns;
unsigned int address_setup_in_cycles;
unsigned int data_setup_in_ns;
unsigned int data_setup_in_cycles;
unsigned int data_hold_in_cycles;
int ideal_sample_delay_in_ns;
unsigned int sample_delay_factor;
int tEYE;
unsigned int min_prop_delay_in_ns = pdata->min_prop_delay_in_ns;
unsigned int max_prop_delay_in_ns = pdata->max_prop_delay_in_ns;
/*
* If there are multiple chips, we need to relax the timings to allow
* for signal distortion due to higher capacitance.
*/
if (nand->numchips > 2) {
target.data_setup_in_ns += 10;
target.data_hold_in_ns += 10;
target.address_setup_in_ns += 10;
} else if (nand->numchips > 1) {
target.data_setup_in_ns += 5;
target.data_hold_in_ns += 5;
target.address_setup_in_ns += 5;
}
/* Check if improved timing information is available. */
improved_timing_is_available =
(target.tREA_in_ns >= 0) &&
(target.tRLOH_in_ns >= 0) &&
(target.tRHOH_in_ns >= 0) ;
/* Inspect the clock. */
clock_frequency_in_hz = nfc->clock_frequency_in_hz;
clock_period_in_ns = 1000000000 / clock_frequency_in_hz;
/*
* The NFC quantizes setup and hold parameters in terms of clock cycles.
* Here, we quantize the setup and hold timing parameters to the
* next-highest clock period to make sure we apply at least the
* specified times.
*
* For data setup and data hold, the hardware interprets a value of zero
* as the largest possible delay. This is not what's intended by a zero
* in the input parameter, so we impose a minimum of one cycle.
*/
data_setup_in_cycles = ns_to_cycles(target.data_setup_in_ns,
clock_period_in_ns, 1);
data_hold_in_cycles = ns_to_cycles(target.data_hold_in_ns,
clock_period_in_ns, 1);
address_setup_in_cycles = ns_to_cycles(target.address_setup_in_ns,
clock_period_in_ns, 0);
/*
* The clock's period affects the sample delay in a number of ways:
*
* (1) The NFC HAL tells us the maximum clock period the sample delay
* DLL can tolerate. If the clock period is greater than half that
* maximum, we must configure the DLL to be driven by half periods.
*
* (2) We need to convert from an ideal sample delay, in ns, to a
* "sample delay factor," which the NFC uses. This factor depends on
* whether we're driving the DLL with full or half periods.
* Paraphrasing the reference manual:
*
* AD = SDF x 0.125 x RP
*
* where:
*
* AD is the applied delay, in ns.
* SDF is the sample delay factor, which is dimensionless.
* RP is the reference period, in ns, which is a full clock period
* if the DLL is being driven by full periods, or half that if
* the DLL is being driven by half periods.
*
* Let's re-arrange this in a way that's more useful to us:
*
* 8
* SDF = AD x ----
* RP
*
* The reference period is either the clock period or half that, so this
* is:
*
* 8 AD x DDF
* SDF = AD x ----- = --------
* f x P P
*
* where:
*
* f is 1 or 1/2, depending on how we're driving the DLL.
* P is the clock period.
* DDF is the DLL Delay Factor, a dimensionless value that
* incorporates all the constants in the conversion.
*
* DDF will be either 8 or 16, both of which are powers of two. We can
* reduce the cost of this conversion by using bit shifts instead of
* multiplication or division. Thus:
*
* AD << DDS
* SDF = ---------
* P
*
* or
*
* AD = (SDF >> DDS) x P
*
* where:
*
* DDS is the DLL Delay Shift, the logarithm to base 2 of the DDF.
*/
if (clock_period_in_ns > (nfc->max_dll_clock_period_in_ns >> 1)) {
dll_use_half_periods = true;
dll_delay_shift = 3 + 1;
} else {
dll_use_half_periods = false;
dll_delay_shift = 3;
}
/*
* Compute the maximum sample delay the NFC allows, under current
* conditions. If the clock is running too slowly, no sample delay is
* possible.
*/
if (clock_period_in_ns > nfc->max_dll_clock_period_in_ns)
max_sample_delay_in_ns = 0;
else {
/*
* Compute the delay implied by the largest sample delay factor
* the NFC allows.
*/
max_sample_delay_in_ns =
(nfc->max_sample_delay_factor * clock_period_in_ns) >>
dll_delay_shift;
/*
* Check if the implied sample delay larger than the NFC
* actually allows.
*/
if (max_sample_delay_in_ns > nfc->max_dll_delay_in_ns)
max_sample_delay_in_ns = nfc->max_dll_delay_in_ns;
}
/*
* Check if improved timing information is available. If not, we have to
* use a less-sophisticated algorithm.
*/
if (!improved_timing_is_available) {
/*
* Fold the read setup time required by the NFC into the ideal
* sample delay.
*/
ideal_sample_delay_in_ns = target.gpmi_sample_delay_in_ns +
nfc->internal_data_setup_in_ns;
/*
* The ideal sample delay may be greater than the maximum
* allowed by the NFC. If so, we can trade off sample delay time
* for more data setup time.
*
* In each iteration of the following loop, we add a cycle to
* the data setup time and subtract a corresponding amount from
* the sample delay until we've satisified the constraints or
* can't do any better.
*/
while ((ideal_sample_delay_in_ns > max_sample_delay_in_ns) &&
(data_setup_in_cycles < nfc->max_data_setup_cycles)) {
data_setup_in_cycles++;
ideal_sample_delay_in_ns -= clock_period_in_ns;
if (ideal_sample_delay_in_ns < 0)
ideal_sample_delay_in_ns = 0;
}
/*
* Compute the sample delay factor that corresponds most closely
* to the ideal sample delay. If the result is too large for the
* NFC, use the maximum value.
*
* Notice that we use the ns_to_cycles function to compute the
* sample delay factor. We do this because the form of the
* computation is the same as that for calculating cycles.
*/
sample_delay_factor =
ns_to_cycles(
ideal_sample_delay_in_ns << dll_delay_shift,
clock_period_in_ns, 0);
if (sample_delay_factor > nfc->max_sample_delay_factor)
sample_delay_factor = nfc->max_sample_delay_factor;
/* Skip to the part where we return our results. */
goto return_results;
}
/*
* If control arrives here, we have more detailed timing information,
* so we can use a better algorithm.
*/
/*
* Fold the read setup time required by the NFC into the maximum
* propagation delay.
*/
max_prop_delay_in_ns += nfc->internal_data_setup_in_ns;
/*
* Earlier, we computed the number of clock cycles required to satisfy
* the data setup time. Now, we need to know the actual nanoseconds.
*/
data_setup_in_ns = clock_period_in_ns * data_setup_in_cycles;
/*
* Compute tEYE, the width of the data eye when reading from the NAND
* Flash. The eye width is fundamentally determined by the data setup
* time, perturbed by propagation delays and some characteristics of the
* NAND Flash device.
*
* start of the eye = max_prop_delay + tREA
* end of the eye = min_prop_delay + tRHOH + data_setup
*/
tEYE = (int)min_prop_delay_in_ns + (int)target.tRHOH_in_ns +
(int)data_setup_in_ns;
tEYE -= (int)max_prop_delay_in_ns + (int)target.tREA_in_ns;
/*
* The eye must be open. If it's not, we can try to open it by
* increasing its main forcer, the data setup time.
*
* In each iteration of the following loop, we increase the data setup
* time by a single clock cycle. We do this until either the eye is
* open or we run into NFC limits.
*/
while ((tEYE <= 0) &&
(data_setup_in_cycles < nfc->max_data_setup_cycles)) {
/* Give a cycle to data setup. */
data_setup_in_cycles++;
/* Synchronize the data setup time with the cycles. */
data_setup_in_ns += clock_period_in_ns;
/* Adjust tEYE accordingly. */
tEYE += clock_period_in_ns;
}
/*
* When control arrives here, the eye is open. The ideal time to sample
* the data is in the center of the eye:
*
* end of the eye + start of the eye
* --------------------------------- - data_setup
* 2
*
* After some algebra, this simplifies to the code immediately below.
*/
ideal_sample_delay_in_ns =
((int)max_prop_delay_in_ns +
(int)target.tREA_in_ns +
(int)min_prop_delay_in_ns +
(int)target.tRHOH_in_ns -
(int)data_setup_in_ns) >> 1;
/*
* The following figure illustrates some aspects of a NAND Flash read:
*
*
* __ _____________________________________
* RDN \_________________/
*
* <---- tEYE ----->
* /-----------------\
* Read Data ----------------------------< >---------
* \-----------------/
* ^ ^ ^ ^
* | | | |
* |<--Data Setup -->|<--Delay Time -->| |
* | | | |
* | | |
* | |<-- Quantized Delay Time -->|
* | | |
*
*
* We have some issues we must now address:
*
* (1) The *ideal* sample delay time must not be negative. If it is, we
* jam it to zero.
*
* (2) The *ideal* sample delay time must not be greater than that
* allowed by the NFC. If it is, we can increase the data setup
* time, which will reduce the delay between the end of the data
* setup and the center of the eye. It will also make the eye
* larger, which might help with the next issue...
*
* (3) The *quantized* sample delay time must not fall either before the
* eye opens or after it closes (the latter is the problem
* illustrated in the above figure).
*/
/* Jam a negative ideal sample delay to zero. */
if (ideal_sample_delay_in_ns < 0)
ideal_sample_delay_in_ns = 0;
/*
* Extend the data setup as needed to reduce the ideal sample delay
* below the maximum permitted by the NFC.
*/
while ((ideal_sample_delay_in_ns > max_sample_delay_in_ns) &&
(data_setup_in_cycles < nfc->max_data_setup_cycles)) {
/* Give a cycle to data setup. */
data_setup_in_cycles++;
/* Synchronize the data setup time with the cycles. */
data_setup_in_ns += clock_period_in_ns;
/* Adjust tEYE accordingly. */
tEYE += clock_period_in_ns;
/*
* Decrease the ideal sample delay by one half cycle, to keep it
* in the middle of the eye.
*/
ideal_sample_delay_in_ns -= (clock_period_in_ns >> 1);
/* Jam a negative ideal sample delay to zero. */
if (ideal_sample_delay_in_ns < 0)
ideal_sample_delay_in_ns = 0;
}
/*
* Compute the sample delay factor that corresponds to the ideal sample
* delay. If the result is too large, then use the maximum allowed
* value.
*
* Notice that we use the ns_to_cycles function to compute the sample
* delay factor. We do this because the form of the computation is the
* same as that for calculating cycles.
*/
sample_delay_factor =
ns_to_cycles(ideal_sample_delay_in_ns << dll_delay_shift,
clock_period_in_ns, 0);
if (sample_delay_factor > nfc->max_sample_delay_factor)
sample_delay_factor = nfc->max_sample_delay_factor;
/*
* These macros conveniently encapsulate a computation we'll use to
* continuously evaluate whether or not the data sample delay is inside
* the eye.
*/
#define IDEAL_DELAY ((int) ideal_sample_delay_in_ns)
#define QUANTIZED_DELAY \
((int) ((sample_delay_factor * clock_period_in_ns) >> \
dll_delay_shift))
#define DELAY_ERROR (abs(QUANTIZED_DELAY - IDEAL_DELAY))
#define SAMPLE_IS_NOT_WITHIN_THE_EYE (DELAY_ERROR > (tEYE >> 1))
/*
* While the quantized sample time falls outside the eye, reduce the
* sample delay or extend the data setup to move the sampling point back
* toward the eye. Do not allow the number of data setup cycles to
* exceed the maximum allowed by the NFC.
*/
while (SAMPLE_IS_NOT_WITHIN_THE_EYE &&
(data_setup_in_cycles < nfc->max_data_setup_cycles)) {
/*
* If control arrives here, the quantized sample delay falls
* outside the eye. Check if it's before the eye opens, or after
* the eye closes.
*/
if (QUANTIZED_DELAY > IDEAL_DELAY) {
/*
* If control arrives here, the quantized sample delay
* falls after the eye closes. Decrease the quantized
* delay time and then go back to re-evaluate.
*/
if (sample_delay_factor != 0)
sample_delay_factor--;
continue;
}
/*
* If control arrives here, the quantized sample delay falls
* before the eye opens. Shift the sample point by increasing
* data setup time. This will also make the eye larger.
*/
/* Give a cycle to data setup. */
data_setup_in_cycles++;
/* Synchronize the data setup time with the cycles. */
data_setup_in_ns += clock_period_in_ns;
/* Adjust tEYE accordingly. */
tEYE += clock_period_in_ns;
/*
* Decrease the ideal sample delay by one half cycle, to keep it
* in the middle of the eye.
*/
ideal_sample_delay_in_ns -= (clock_period_in_ns >> 1);
/* ...and one less period for the delay time. */
ideal_sample_delay_in_ns -= clock_period_in_ns;
/* Jam a negative ideal sample delay to zero. */
if (ideal_sample_delay_in_ns < 0)
ideal_sample_delay_in_ns = 0;
/*
* We have a new ideal sample delay, so re-compute the quantized
* delay.
*/
sample_delay_factor =
ns_to_cycles(
ideal_sample_delay_in_ns << dll_delay_shift,
clock_period_in_ns, 0);
if (sample_delay_factor > nfc->max_sample_delay_factor)
sample_delay_factor = nfc->max_sample_delay_factor;
}
/* Control arrives here when we're ready to return our results. */
return_results:
hw->data_setup_in_cycles = data_setup_in_cycles;
hw->data_hold_in_cycles = data_hold_in_cycles;
hw->address_setup_in_cycles = address_setup_in_cycles;
hw->use_half_periods = dll_use_half_periods;
hw->sample_delay_factor = sample_delay_factor;
/* Return success. */
return 0;
}
/* Begin the I/O */
void gpmi_begin(struct gpmi_nand_data *this)
{
struct resources *r = &this->resources;
struct timing_threshod *nfc = &timing_default_threshold;
unsigned char *gpmi_regs = r->gpmi_regs;
unsigned int clock_period_in_ns;
uint32_t reg;
unsigned int dll_wait_time_in_us;
struct gpmi_nfc_hardware_timing hw;
int ret;
/* Enable the clock. */
ret = clk_prepare_enable(r->clock);
if (ret) {
pr_err("We failed in enable the clk\n");
goto err_out;
}
/* set ready/busy timeout */
writel(0x500 << BP_GPMI_TIMING1_BUSY_TIMEOUT,
gpmi_regs + HW_GPMI_TIMING1);
/* Get the timing information we need. */
nfc->clock_frequency_in_hz = clk_get_rate(r->clock);
clock_period_in_ns = 1000000000 / nfc->clock_frequency_in_hz;
gpmi_nfc_compute_hardware_timing(this, &hw);
/* Set up all the simple timing parameters. */
reg = BF_GPMI_TIMING0_ADDRESS_SETUP(hw.address_setup_in_cycles) |
BF_GPMI_TIMING0_DATA_HOLD(hw.data_hold_in_cycles) |
BF_GPMI_TIMING0_DATA_SETUP(hw.data_setup_in_cycles) ;
writel(reg, gpmi_regs + HW_GPMI_TIMING0);
/*
* DLL_ENABLE must be set to 0 when setting RDN_DELAY or HALF_PERIOD.
*/
writel(BM_GPMI_CTRL1_DLL_ENABLE, gpmi_regs + HW_GPMI_CTRL1_CLR);
/* Clear out the DLL control fields. */
writel(BM_GPMI_CTRL1_RDN_DELAY, gpmi_regs + HW_GPMI_CTRL1_CLR);
writel(BM_GPMI_CTRL1_HALF_PERIOD, gpmi_regs + HW_GPMI_CTRL1_CLR);
/* If no sample delay is called for, return immediately. */
if (!hw.sample_delay_factor)
return;
/* Configure the HALF_PERIOD flag. */
if (hw.use_half_periods)
writel(BM_GPMI_CTRL1_HALF_PERIOD,
gpmi_regs + HW_GPMI_CTRL1_SET);
/* Set the delay factor. */
writel(BF_GPMI_CTRL1_RDN_DELAY(hw.sample_delay_factor),
gpmi_regs + HW_GPMI_CTRL1_SET);
/* Enable the DLL. */
writel(BM_GPMI_CTRL1_DLL_ENABLE, gpmi_regs + HW_GPMI_CTRL1_SET);
/*
* After we enable the GPMI DLL, we have to wait 64 clock cycles before
* we can use the GPMI.
*
* Calculate the amount of time we need to wait, in microseconds.
*/
dll_wait_time_in_us = (clock_period_in_ns * 64) / 1000;
if (!dll_wait_time_in_us)
dll_wait_time_in_us = 1;
/* Wait for the DLL to settle. */
udelay(dll_wait_time_in_us);
err_out:
return;
}
void gpmi_end(struct gpmi_nand_data *this)
{
struct resources *r = &this->resources;
clk_disable_unprepare(r->clock);
}
/* Clears a BCH interrupt. */
void gpmi_clear_bch(struct gpmi_nand_data *this)
{
struct resources *r = &this->resources;
writel(BM_BCH_CTRL_COMPLETE_IRQ, r->bch_regs + HW_BCH_CTRL_CLR);
}
/* Returns the Ready/Busy status of the given chip. */
int gpmi_is_ready(struct gpmi_nand_data *this, unsigned chip)
{
struct resources *r = &this->resources;
uint32_t mask = 0;
uint32_t reg = 0;
if (GPMI_IS_MX23(this)) {
mask = MX23_BM_GPMI_DEBUG_READY0 << chip;
reg = readl(r->gpmi_regs + HW_GPMI_DEBUG);
} else if (GPMI_IS_MX28(this)) {
mask = MX28_BF_GPMI_STAT_READY_BUSY(1 << chip);
reg = readl(r->gpmi_regs + HW_GPMI_STAT);
} else
pr_err("unknow arch.\n");
return reg & mask;
}
static inline void set_dma_type(struct gpmi_nand_data *this,
enum dma_ops_type type)
{
this->last_dma_type = this->dma_type;
this->dma_type = type;
}
int gpmi_send_command(struct gpmi_nand_data *this)
{
struct dma_chan *channel = get_dma_chan(this);
struct dma_async_tx_descriptor *desc;
struct scatterlist *sgl;
int chip = this->current_chip;
u32 pio[3];
/* [1] send out the PIO words */
pio[0] = BF_GPMI_CTRL0_COMMAND_MODE(BV_GPMI_CTRL0_COMMAND_MODE__WRITE)
| BM_GPMI_CTRL0_WORD_LENGTH
| BF_GPMI_CTRL0_CS(chip, this)
| BF_GPMI_CTRL0_LOCK_CS(LOCK_CS_ENABLE, this)
| BF_GPMI_CTRL0_ADDRESS(BV_GPMI_CTRL0_ADDRESS__NAND_CLE)
| BM_GPMI_CTRL0_ADDRESS_INCREMENT
| BF_GPMI_CTRL0_XFER_COUNT(this->command_length);
pio[1] = pio[2] = 0;
desc = channel->device->device_prep_slave_sg(channel,
(struct scatterlist *)pio,
ARRAY_SIZE(pio), DMA_TRANS_NONE, 0);
if (!desc) {
pr_err("step 1 error\n");
return -1;
}
/* [2] send out the COMMAND + ADDRESS string stored in @buffer */
sgl = &this->cmd_sgl;
sg_init_one(sgl, this->cmd_buffer, this->command_length);
dma_map_sg(this->dev, sgl, 1, DMA_TO_DEVICE);
desc = channel->device->device_prep_slave_sg(channel,
sgl, 1, DMA_MEM_TO_DEV, 1);
if (!desc) {
pr_err("step 2 error\n");
return -1;
}
/* [3] submit the DMA */
set_dma_type(this, DMA_FOR_COMMAND);
return start_dma_without_bch_irq(this, desc);
}
int gpmi_send_data(struct gpmi_nand_data *this)
{
struct dma_async_tx_descriptor *desc;
struct dma_chan *channel = get_dma_chan(this);
int chip = this->current_chip;
uint32_t command_mode;
uint32_t address;
u32 pio[2];
/* [1] PIO */
command_mode = BV_GPMI_CTRL0_COMMAND_MODE__WRITE;
address = BV_GPMI_CTRL0_ADDRESS__NAND_DATA;
pio[0] = BF_GPMI_CTRL0_COMMAND_MODE(command_mode)
| BM_GPMI_CTRL0_WORD_LENGTH
| BF_GPMI_CTRL0_CS(chip, this)
| BF_GPMI_CTRL0_LOCK_CS(LOCK_CS_ENABLE, this)
| BF_GPMI_CTRL0_ADDRESS(address)
| BF_GPMI_CTRL0_XFER_COUNT(this->upper_len);
pio[1] = 0;
desc = channel->device->device_prep_slave_sg(channel,
(struct scatterlist *)pio,
ARRAY_SIZE(pio), DMA_TRANS_NONE, 0);
if (!desc) {
pr_err("step 1 error\n");
return -1;
}
/* [2] send DMA request */
prepare_data_dma(this, DMA_TO_DEVICE);
desc = channel->device->device_prep_slave_sg(channel, &this->data_sgl,
1, DMA_MEM_TO_DEV, 1);
if (!desc) {
pr_err("step 2 error\n");
return -1;
}
/* [3] submit the DMA */
set_dma_type(this, DMA_FOR_WRITE_DATA);
return start_dma_without_bch_irq(this, desc);
}
int gpmi_read_data(struct gpmi_nand_data *this)
{
struct dma_async_tx_descriptor *desc;
struct dma_chan *channel = get_dma_chan(this);
int chip = this->current_chip;
u32 pio[2];
/* [1] : send PIO */
pio[0] = BF_GPMI_CTRL0_COMMAND_MODE(BV_GPMI_CTRL0_COMMAND_MODE__READ)
| BM_GPMI_CTRL0_WORD_LENGTH
| BF_GPMI_CTRL0_CS(chip, this)
| BF_GPMI_CTRL0_LOCK_CS(LOCK_CS_ENABLE, this)
| BF_GPMI_CTRL0_ADDRESS(BV_GPMI_CTRL0_ADDRESS__NAND_DATA)
| BF_GPMI_CTRL0_XFER_COUNT(this->upper_len);
pio[1] = 0;
desc = channel->device->device_prep_slave_sg(channel,
(struct scatterlist *)pio,
ARRAY_SIZE(pio), DMA_TRANS_NONE, 0);
if (!desc) {
pr_err("step 1 error\n");
return -1;
}
/* [2] : send DMA request */
prepare_data_dma(this, DMA_FROM_DEVICE);
desc = channel->device->device_prep_slave_sg(channel, &this->data_sgl,
1, DMA_DEV_TO_MEM, 1);
if (!desc) {
pr_err("step 2 error\n");
return -1;
}
/* [3] : submit the DMA */
set_dma_type(this, DMA_FOR_READ_DATA);
return start_dma_without_bch_irq(this, desc);
}
int gpmi_send_page(struct gpmi_nand_data *this,
dma_addr_t payload, dma_addr_t auxiliary)
{
struct bch_geometry *geo = &this->bch_geometry;
uint32_t command_mode;
uint32_t address;
uint32_t ecc_command;
uint32_t buffer_mask;
struct dma_async_tx_descriptor *desc;
struct dma_chan *channel = get_dma_chan(this);
int chip = this->current_chip;
u32 pio[6];
/* A DMA descriptor that does an ECC page read. */
command_mode = BV_GPMI_CTRL0_COMMAND_MODE__WRITE;
address = BV_GPMI_CTRL0_ADDRESS__NAND_DATA;
ecc_command = BV_GPMI_ECCCTRL_ECC_CMD__BCH_ENCODE;
buffer_mask = BV_GPMI_ECCCTRL_BUFFER_MASK__BCH_PAGE |
BV_GPMI_ECCCTRL_BUFFER_MASK__BCH_AUXONLY;
pio[0] = BF_GPMI_CTRL0_COMMAND_MODE(command_mode)
| BM_GPMI_CTRL0_WORD_LENGTH
| BF_GPMI_CTRL0_CS(chip, this)
| BF_GPMI_CTRL0_LOCK_CS(LOCK_CS_ENABLE, this)
| BF_GPMI_CTRL0_ADDRESS(address)
| BF_GPMI_CTRL0_XFER_COUNT(0);
pio[1] = 0;
pio[2] = BM_GPMI_ECCCTRL_ENABLE_ECC
| BF_GPMI_ECCCTRL_ECC_CMD(ecc_command)
| BF_GPMI_ECCCTRL_BUFFER_MASK(buffer_mask);
pio[3] = geo->page_size;
pio[4] = payload;
pio[5] = auxiliary;
desc = channel->device->device_prep_slave_sg(channel,
(struct scatterlist *)pio,
ARRAY_SIZE(pio), DMA_TRANS_NONE, 0);
if (!desc) {
pr_err("step 2 error\n");
return -1;
}
set_dma_type(this, DMA_FOR_WRITE_ECC_PAGE);
return start_dma_with_bch_irq(this, desc);
}
int gpmi_read_page(struct gpmi_nand_data *this,
dma_addr_t payload, dma_addr_t auxiliary)
{
struct bch_geometry *geo = &this->bch_geometry;
uint32_t command_mode;
uint32_t address;
uint32_t ecc_command;
uint32_t buffer_mask;
struct dma_async_tx_descriptor *desc;
struct dma_chan *channel = get_dma_chan(this);
int chip = this->current_chip;
u32 pio[6];
/* [1] Wait for the chip to report ready. */
command_mode = BV_GPMI_CTRL0_COMMAND_MODE__WAIT_FOR_READY;
address = BV_GPMI_CTRL0_ADDRESS__NAND_DATA;
pio[0] = BF_GPMI_CTRL0_COMMAND_MODE(command_mode)
| BM_GPMI_CTRL0_WORD_LENGTH
| BF_GPMI_CTRL0_CS(chip, this)
| BF_GPMI_CTRL0_LOCK_CS(LOCK_CS_ENABLE, this)
| BF_GPMI_CTRL0_ADDRESS(address)
| BF_GPMI_CTRL0_XFER_COUNT(0);
pio[1] = 0;
desc = channel->device->device_prep_slave_sg(channel,
(struct scatterlist *)pio, 2,
DMA_TRANS_NONE, 0);
if (!desc) {
pr_err("step 1 error\n");
return -1;
}
/* [2] Enable the BCH block and read. */
command_mode = BV_GPMI_CTRL0_COMMAND_MODE__READ;
address = BV_GPMI_CTRL0_ADDRESS__NAND_DATA;
ecc_command = BV_GPMI_ECCCTRL_ECC_CMD__BCH_DECODE;
buffer_mask = BV_GPMI_ECCCTRL_BUFFER_MASK__BCH_PAGE
| BV_GPMI_ECCCTRL_BUFFER_MASK__BCH_AUXONLY;
pio[0] = BF_GPMI_CTRL0_COMMAND_MODE(command_mode)
| BM_GPMI_CTRL0_WORD_LENGTH
| BF_GPMI_CTRL0_CS(chip, this)
| BF_GPMI_CTRL0_LOCK_CS(LOCK_CS_ENABLE, this)
| BF_GPMI_CTRL0_ADDRESS(address)
| BF_GPMI_CTRL0_XFER_COUNT(geo->page_size);
pio[1] = 0;
pio[2] = BM_GPMI_ECCCTRL_ENABLE_ECC
| BF_GPMI_ECCCTRL_ECC_CMD(ecc_command)
| BF_GPMI_ECCCTRL_BUFFER_MASK(buffer_mask);
pio[3] = geo->page_size;
pio[4] = payload;
pio[5] = auxiliary;
desc = channel->device->device_prep_slave_sg(channel,
(struct scatterlist *)pio,
ARRAY_SIZE(pio), DMA_TRANS_NONE, 1);
if (!desc) {
pr_err("step 2 error\n");
return -1;
}
/* [3] Disable the BCH block */
command_mode = BV_GPMI_CTRL0_COMMAND_MODE__WAIT_FOR_READY;
address = BV_GPMI_CTRL0_ADDRESS__NAND_DATA;
pio[0] = BF_GPMI_CTRL0_COMMAND_MODE(command_mode)
| BM_GPMI_CTRL0_WORD_LENGTH
| BF_GPMI_CTRL0_CS(chip, this)
| BF_GPMI_CTRL0_LOCK_CS(LOCK_CS_ENABLE, this)
| BF_GPMI_CTRL0_ADDRESS(address)
| BF_GPMI_CTRL0_XFER_COUNT(geo->page_size);
pio[1] = 0;
desc = channel->device->device_prep_slave_sg(channel,
(struct scatterlist *)pio, 2,
DMA_TRANS_NONE, 1);
if (!desc) {
pr_err("step 3 error\n");
return -1;
}
/* [4] submit the DMA */
set_dma_type(this, DMA_FOR_READ_ECC_PAGE);
return start_dma_with_bch_irq(this, desc);
}