bcm53xx: replace SPI revert with a fix sent upstream
Instead of reverting whole commit it's enough to just revert a single line change. It seems the real problem with the regressing commit was a bump of read chunk size. Switching back to 256 B chunks is enough to fix the problem/regression. Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
This commit is contained in:
Rafał Miłecki
parent
d24bdaa794
commit
92de28b751
|
|
@ -0,0 +1,42 @@
|
|||
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
|
||||
Date: Thu, 11 Oct 2018 09:07:31 +0200
|
||||
Subject: [PATCH FIX] spi: bcm-qspi: switch back to reading flash using smaller
|
||||
chunks
|
||||
MIME-Version: 1.0
|
||||
Content-Type: text/plain; charset=UTF-8
|
||||
Content-Transfer-Encoding: 8bit
|
||||
|
||||
Fixing/optimizing bcm_qspi_bspi_read() performance introduced two
|
||||
changes:
|
||||
1) It added a loop to read all requested data using multiple BSPI ops.
|
||||
2) It bumped max size of a single BSPI block request from 256 to 512 B.
|
||||
|
||||
The later change resulted in occasional BSPI timeouts causing a
|
||||
regression.
|
||||
|
||||
For some unknown reason hardware doesn't always handle reads as expected
|
||||
when using 512 B chunks. In such cases it may happen that BSPI returns
|
||||
amount of requested bytes without the last 1-3 ones. It provides the
|
||||
remaining bytes later but doesn't raise an interrupt until another LR
|
||||
start.
|
||||
|
||||
Switching back to 256 B reads fixes that problem and regression.
|
||||
|
||||
Fixes: 345309fa7c0c ("spi: bcm-qspi: Fix bcm_qspi_bspi_read() performance")
|
||||
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
|
||||
Cc: stable@vger.kernel.org # 4.11+
|
||||
---
|
||||
drivers/spi/spi-bcm-qspi.c | 2 +-
|
||||
1 file changed, 1 insertion(+), 1 deletion(-)
|
||||
|
||||
--- a/drivers/spi/spi-bcm-qspi.c
|
||||
+++ b/drivers/spi/spi-bcm-qspi.c
|
||||
@@ -88,7 +88,7 @@
|
||||
#define BSPI_BPP_MODE_SELECT_MASK BIT(8)
|
||||
#define BSPI_BPP_ADDR_SELECT_MASK BIT(16)
|
||||
|
||||
-#define BSPI_READ_LENGTH 512
|
||||
+#define BSPI_READ_LENGTH 256
|
||||
|
||||
/* MSPI register offsets */
|
||||
#define MSPI_SPCR0_LSB 0x000
|
||||
|
|
@ -1,146 +0,0 @@
|
|||
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
|
||||
Subject: [PATCH] Revert "spi: bcm-qspi: Fix bcm_qspi_bspi_read() performance"
|
||||
MIME-Version: 1.0
|
||||
Content-Type: text/plain; charset=UTF-8
|
||||
Content-Transfer-Encoding: 8bit
|
||||
|
||||
This reverts commit 345309fa7c0c9206a5344d379b174499952d79d9.
|
||||
|
||||
BSPI reads became unstable starting with above commit. There are BSPI
|
||||
timeouts like this:
|
||||
[ 15.637809] bcm_iproc 18029200.spi: timeout waiting for BSPI
|
||||
(...)
|
||||
[ 15.997809] bcm_iproc 18029200.spi: timeout waiting for BSPI
|
||||
which cause filesystem stability problems.
|
||||
|
||||
Before above commit every time that bcm_qspi_bspi_lr_l2_isr() called
|
||||
bcm_qspi_bspi_lr_l2_isr() it was resulting in bspi_rf_msg_len becoming
|
||||
0.
|
||||
With that change it's not the case anymore which suggests there may be
|
||||
some bug around that code.
|
||||
|
||||
It has changed and the new behavior seems to be causing problems.
|
||||
|
||||
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
|
||||
---
|
||||
|
||||
--- a/drivers/spi/spi-bcm-qspi.c
|
||||
+++ b/drivers/spi/spi-bcm-qspi.c
|
||||
@@ -88,7 +88,7 @@
|
||||
#define BSPI_BPP_MODE_SELECT_MASK BIT(8)
|
||||
#define BSPI_BPP_ADDR_SELECT_MASK BIT(16)
|
||||
|
||||
-#define BSPI_READ_LENGTH 512
|
||||
+#define BSPI_READ_LENGTH 256
|
||||
|
||||
/* MSPI register offsets */
|
||||
#define MSPI_SPCR0_LSB 0x000
|
||||
@@ -806,7 +806,7 @@ static int bcm_qspi_bspi_flash_read(stru
|
||||
struct spi_flash_read_message *msg)
|
||||
{
|
||||
struct bcm_qspi *qspi = spi_master_get_devdata(spi->master);
|
||||
- u32 addr = 0, len, rdlen, len_words;
|
||||
+ u32 addr = 0, len, len_words;
|
||||
int ret = 0;
|
||||
unsigned long timeo = msecs_to_jiffies(100);
|
||||
struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;
|
||||
@@ -819,7 +819,7 @@ static int bcm_qspi_bspi_flash_read(stru
|
||||
bcm_qspi_write(qspi, MSPI, MSPI_WRITE_LOCK, 0);
|
||||
|
||||
/*
|
||||
- * when using flex mode we need to send
|
||||
+ * when using flex mode mode we need to send
|
||||
* the upper address byte to bspi
|
||||
*/
|
||||
if (bcm_qspi_bspi_ver_three(qspi) == false) {
|
||||
@@ -833,56 +833,47 @@ static int bcm_qspi_bspi_flash_read(stru
|
||||
else
|
||||
addr = msg->from & 0x00ffffff;
|
||||
|
||||
+ /* set BSPI RAF buffer max read length */
|
||||
+ len = msg->len;
|
||||
+ if (len > BSPI_READ_LENGTH)
|
||||
+ len = BSPI_READ_LENGTH;
|
||||
+
|
||||
if (bcm_qspi_bspi_ver_three(qspi) == true)
|
||||
addr = (addr + 0xc00000) & 0xffffff;
|
||||
|
||||
- /*
|
||||
- * read into the entire buffer by breaking the reads
|
||||
- * into RAF buffer read lengths
|
||||
- */
|
||||
- len = msg->len;
|
||||
+ reinit_completion(&qspi->bspi_done);
|
||||
+ bcm_qspi_enable_bspi(qspi);
|
||||
+ len_words = (len + 3) >> 2;
|
||||
+ qspi->bspi_rf_msg = msg;
|
||||
+ qspi->bspi_rf_msg_status = 0;
|
||||
qspi->bspi_rf_msg_idx = 0;
|
||||
+ qspi->bspi_rf_msg_len = len;
|
||||
+ dev_dbg(&qspi->pdev->dev, "bspi xfr addr 0x%x len 0x%x", addr, len);
|
||||
|
||||
- do {
|
||||
- if (len > BSPI_READ_LENGTH)
|
||||
- rdlen = BSPI_READ_LENGTH;
|
||||
- else
|
||||
- rdlen = len;
|
||||
-
|
||||
- reinit_completion(&qspi->bspi_done);
|
||||
- bcm_qspi_enable_bspi(qspi);
|
||||
- len_words = (rdlen + 3) >> 2;
|
||||
- qspi->bspi_rf_msg = msg;
|
||||
- qspi->bspi_rf_msg_status = 0;
|
||||
- qspi->bspi_rf_msg_len = rdlen;
|
||||
- dev_dbg(&qspi->pdev->dev,
|
||||
- "bspi xfr addr 0x%x len 0x%x", addr, rdlen);
|
||||
- bcm_qspi_write(qspi, BSPI, BSPI_RAF_START_ADDR, addr);
|
||||
- bcm_qspi_write(qspi, BSPI, BSPI_RAF_NUM_WORDS, len_words);
|
||||
- bcm_qspi_write(qspi, BSPI, BSPI_RAF_WATERMARK, 0);
|
||||
- if (qspi->soc_intc) {
|
||||
- /*
|
||||
- * clear soc MSPI and BSPI interrupts and enable
|
||||
- * BSPI interrupts.
|
||||
- */
|
||||
- soc_intc->bcm_qspi_int_ack(soc_intc, MSPI_BSPI_DONE);
|
||||
- soc_intc->bcm_qspi_int_set(soc_intc, BSPI_DONE, true);
|
||||
- }
|
||||
+ bcm_qspi_write(qspi, BSPI, BSPI_RAF_START_ADDR, addr);
|
||||
+ bcm_qspi_write(qspi, BSPI, BSPI_RAF_NUM_WORDS, len_words);
|
||||
+ bcm_qspi_write(qspi, BSPI, BSPI_RAF_WATERMARK, 0);
|
||||
+
|
||||
+ if (qspi->soc_intc) {
|
||||
+ /*
|
||||
+ * clear soc MSPI and BSPI interrupts and enable
|
||||
+ * BSPI interrupts.
|
||||
+ */
|
||||
+ soc_intc->bcm_qspi_int_ack(soc_intc, MSPI_BSPI_DONE);
|
||||
+ soc_intc->bcm_qspi_int_set(soc_intc, BSPI_DONE, true);
|
||||
+ }
|
||||
|
||||
- /* Must flush previous writes before starting BSPI operation */
|
||||
- mb();
|
||||
- bcm_qspi_bspi_lr_start(qspi);
|
||||
- if (!wait_for_completion_timeout(&qspi->bspi_done, timeo)) {
|
||||
- dev_err(&qspi->pdev->dev, "timeout waiting for BSPI\n");
|
||||
- ret = -ETIMEDOUT;
|
||||
- break;
|
||||
- }
|
||||
+ /* Must flush previous writes before starting BSPI operation */
|
||||
+ mb();
|
||||
|
||||
- /* set msg return length */
|
||||
- msg->retlen += rdlen;
|
||||
- addr += rdlen;
|
||||
- len -= rdlen;
|
||||
- } while (len);
|
||||
+ bcm_qspi_bspi_lr_start(qspi);
|
||||
+ if (!wait_for_completion_timeout(&qspi->bspi_done, timeo)) {
|
||||
+ dev_err(&qspi->pdev->dev, "timeout waiting for BSPI\n");
|
||||
+ ret = -ETIMEDOUT;
|
||||
+ } else {
|
||||
+ /* set the return length for the caller */
|
||||
+ msg->retlen = len;
|
||||
+ }
|
||||
|
||||
return ret;
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user