From ba1aa4e33b7861b429b55f57bc11b83aac47d460 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sun, 31 Jul 2016 20:30:08 +0200 Subject: [PATCH] mvebu: fix NAND flash issues (FS#67) Remove the previous PIO delay patch and add a revert patch for a faulty upstream commit, which seems to have introduced this issue in the first place Signed-off-by: Felix Fietkau --- .../110-pxa3xxx_nand-handle-PIO-delays.patch | 36 ---------- .../110-pxa3xxx_revert_irq_thread.patch | 69 +++++++++++++++++++ 2 files changed, 69 insertions(+), 36 deletions(-) delete mode 100644 target/linux/mvebu/patches-4.4/110-pxa3xxx_nand-handle-PIO-delays.patch create mode 100644 target/linux/mvebu/patches-4.4/110-pxa3xxx_revert_irq_thread.patch diff --git a/target/linux/mvebu/patches-4.4/110-pxa3xxx_nand-handle-PIO-delays.patch b/target/linux/mvebu/patches-4.4/110-pxa3xxx_nand-handle-PIO-delays.patch deleted file mode 100644 index 7fa56970c1..0000000000 --- a/target/linux/mvebu/patches-4.4/110-pxa3xxx_nand-handle-PIO-delays.patch +++ /dev/null @@ -1,36 +0,0 @@ -Handle delays/excessive latency during flash command processing with PIO. - -Signed-off-by: Felix Fietkau - ---- a/drivers/mtd/nand/pxa3xx_nand.c -+++ b/drivers/mtd/nand/pxa3xx_nand.c -@@ -227,6 +227,7 @@ struct pxa3xx_nand_info { - int use_dma; /* use DMA ? */ - int use_spare; /* use spare ? */ - int need_wait; -+ int pio_progress; - - /* Amount of real data per full chunk */ - unsigned int chunk_size; -@@ -769,6 +770,7 @@ static irqreturn_t pxa3xx_nand_irq_threa - { - struct pxa3xx_nand_info *info = data; - -+ info->pio_progress = 1; - handle_data_pio(info); - - info->state = STATE_CMD_DONE; -@@ -1175,8 +1177,13 @@ static void nand_cmdfunc(struct mtd_info - info->need_wait = 1; - pxa3xx_nand_start(info); - -+retry: -+ info->pio_progress = 0; - if (!wait_for_completion_timeout(&info->cmd_complete, - CHIP_DELAY_TIMEOUT)) { -+ if (info->pio_progress) -+ goto retry; -+ - dev_err(&info->pdev->dev, "Wait time out!!!\n"); - /* Stop State Machine for next command cycle */ - pxa3xx_nand_stop(info); diff --git a/target/linux/mvebu/patches-4.4/110-pxa3xxx_revert_irq_thread.patch b/target/linux/mvebu/patches-4.4/110-pxa3xxx_revert_irq_thread.patch new file mode 100644 index 0000000000..30da17deb9 --- /dev/null +++ b/target/linux/mvebu/patches-4.4/110-pxa3xxx_revert_irq_thread.patch @@ -0,0 +1,69 @@ +Revert "mtd: pxa3xx-nand: handle PIO in threaded interrupt" + +This reverts commit 24542257a3b987025d4b998ec2d15e556c98ad3f +This upstream change has been causing spurious timeouts on accesses +to the NAND flash if something else on the system is causing +significant latency. + +Nothing guarantees that the thread will run in time, so the +usual timeout is unreliable. + +Signed-off-by: Felix Fietkau + +--- a/drivers/mtd/nand/pxa3xx_nand.c ++++ b/drivers/mtd/nand/pxa3xx_nand.c +@@ -765,24 +765,11 @@ static void start_data_dma(struct pxa3xx + __func__, direction, info->dma_cookie, info->sg.length); + } + +-static irqreturn_t pxa3xx_nand_irq_thread(int irq, void *data) +-{ +- struct pxa3xx_nand_info *info = data; +- +- handle_data_pio(info); +- +- info->state = STATE_CMD_DONE; +- nand_writel(info, NDSR, NDSR_WRDREQ | NDSR_RDDREQ); +- +- return IRQ_HANDLED; +-} +- + static irqreturn_t pxa3xx_nand_irq(int irq, void *devid) + { + struct pxa3xx_nand_info *info = devid; + unsigned int status, is_completed = 0, is_ready = 0; + unsigned int ready, cmd_done; +- irqreturn_t ret = IRQ_HANDLED; + + if (info->cs == 0) { + ready = NDSR_FLASH_RDY; +@@ -824,8 +811,7 @@ static irqreturn_t pxa3xx_nand_irq(int i + } else { + info->state = (status & NDSR_RDDREQ) ? + STATE_PIO_READING : STATE_PIO_WRITING; +- ret = IRQ_WAKE_THREAD; +- goto NORMAL_IRQ_EXIT; ++ handle_data_pio(info); + } + } + if (status & cmd_done) { +@@ -870,7 +856,7 @@ static irqreturn_t pxa3xx_nand_irq(int i + if (is_ready) + complete(&info->dev_ready); + NORMAL_IRQ_EXIT: +- return ret; ++ return IRQ_HANDLED; + } + + static inline int is_buf_blank(uint8_t *buf, size_t len) +@@ -1849,9 +1835,7 @@ static int alloc_nand_resource(struct pl + /* initialize all interrupts to be disabled */ + disable_int(info, NDSR_MASK); + +- ret = request_threaded_irq(irq, pxa3xx_nand_irq, +- pxa3xx_nand_irq_thread, IRQF_ONESHOT, +- pdev->name, info); ++ ret = request_irq(irq, pxa3xx_nand_irq, 0, pdev->name, info); + if (ret < 0) { + dev_err(&pdev->dev, "failed to request IRQ\n"); + goto fail_free_buf; -- 2.25.1