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authorRafał Miłecki <rafal@milecki.pl>2018-07-29 11:01:14 +0200
committerRafał Miłecki <rafal@milecki.pl>2018-07-29 11:10:03 +0200
commitca0c649a380c4bd1d356bf5518f4da47b2b163c1 (patch)
tree7a4f6d5e70bb7c90c4c12018c67af0bf75d3099c
parentcf5a892430d34a4ecca279e11c663b48c3b3d6d2 (diff)
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bcm53xx: revert SPI controller commit breaking flash reads
That upstream commit caused instability in flash reads. It was reported but there isn't any proper fix as for now. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> (cherry picked from commit 0417b08b06dd946c2670d0a19e3426c61e33f6be)
-rw-r--r--target/linux/bcm53xx/patches-4.14/800-Revert-spi-bcm-qspi-Fix-bcm_qspi_bspi_read-performan.patch146
1 files changed, 146 insertions, 0 deletions
diff --git a/target/linux/bcm53xx/patches-4.14/800-Revert-spi-bcm-qspi-Fix-bcm_qspi_bspi_read-performan.patch b/target/linux/bcm53xx/patches-4.14/800-Revert-spi-bcm-qspi-Fix-bcm_qspi_bspi_read-performan.patch
new file mode 100644
index 0000000..64f971d
--- /dev/null
+++ b/target/linux/bcm53xx/patches-4.14/800-Revert-spi-bcm-qspi-Fix-bcm_qspi_bspi_read-performan.patch
@@ -0,0 +1,146 @@
+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;
+ }