From a3d4bfb427fb6e8c9396a744879796231deabc3d Mon Sep 17 00:00:00 2001 From: Ashok Reddy Soma Date: Thu, 25 Aug 2022 06:59:04 -0600 Subject: [PATCH] spi: zynqmp_gqspi: Fix issue of reading more than 32bits length As the flash sizes are increasing day by day, QSPI can have devices of size > 512MB. In qspi driver we are trying to read all the data at once using DMA. The DMA descriptor destination size is only 29bits long. QSPIDMA_DST_SIZE 0xFF0F0804 BITS: 1:0 Reserved to keep word alignment BITS: 28:2 Number of 4-byte words the DMA will transfer BITS: 31:29 Reserved: Returns 0 when read, writes ignored So we can only transfer data of 0x1FFFFFF0(512MB minus 4bytes) bytes. Anything above will overflow this register and will ignore higher bits above 29 bits. Change the DMA functionality if the requested size is greater than or equal to 512MB to read 256MB chunks. Signed-off-by: Ashok Reddy Soma Link: https://lore.kernel.org/r/20220825125906.11581-5-ashok.reddy.soma@amd.com Signed-off-by: Michal Simek --- drivers/spi/zynqmp_gqspi.c | 62 +++++++++++++++++++++++++++++----------------- 1 file changed, 39 insertions(+), 23 deletions(-) diff --git a/drivers/spi/zynqmp_gqspi.c b/drivers/spi/zynqmp_gqspi.c index 78a1b48..d5ccb48 100644 --- a/drivers/spi/zynqmp_gqspi.c +++ b/drivers/spi/zynqmp_gqspi.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #define GQSPI_GFIFO_STRT_MODE_MASK BIT(29) @@ -666,38 +667,53 @@ static int zynqmp_qspi_start_dma(struct zynqmp_qspi_priv *priv, u32 addr; u32 size; u32 actuallen = priv->len; + u32 totallen = priv->len; int ret = 0; struct zynqmp_qspi_dma_regs *dma_regs = priv->dma_regs; - writel((unsigned long)buf, &dma_regs->dmadst); - writel(roundup(priv->len, GQSPI_DMA_ALIGN), &dma_regs->dmasize); - writel(GQSPI_DMA_DST_I_STS_MASK, &dma_regs->dmaier); - addr = (unsigned long)buf; - size = roundup(priv->len, GQSPI_DMA_ALIGN); - flush_dcache_range(addr, addr + size); + while (totallen) { + if (totallen >= SZ_512M) + priv->len = SZ_256M; + else + priv->len = totallen; - while (priv->len) { - zynqmp_qspi_calc_exp(priv, &gen_fifo_cmd); - zynqmp_qspi_fill_gen_fifo(priv, gen_fifo_cmd); + totallen -= priv->len; /* Save remaining bytes length to read */ + actuallen = priv->len; /* Actual number of bytes reading */ - debug("GFIFO_CMD_RX:0x%x\n", gen_fifo_cmd); - } + writel((unsigned long)buf, &dma_regs->dmadst); + writel(roundup(priv->len, GQSPI_DMA_ALIGN), &dma_regs->dmasize); + writel(GQSPI_DMA_DST_I_STS_MASK, &dma_regs->dmaier); + addr = (unsigned long)buf; + size = roundup(priv->len, GQSPI_DMA_ALIGN); + flush_dcache_range(addr, addr + size); - ret = wait_for_bit_le32(&dma_regs->dmaisr, GQSPI_DMA_DST_I_STS_DONE, - 1, GQSPI_TIMEOUT, 1); - if (ret) { - printf("DMA Timeout:0x%x\n", readl(&dma_regs->dmaisr)); - return -ETIMEDOUT; - } + while (priv->len) { + zynqmp_qspi_calc_exp(priv, &gen_fifo_cmd); + zynqmp_qspi_fill_gen_fifo(priv, gen_fifo_cmd); + + debug("GFIFO_CMD_RX:0x%x\n", gen_fifo_cmd); + } + + ret = wait_for_bit_le32(&dma_regs->dmaisr, + GQSPI_DMA_DST_I_STS_DONE, 1, + GQSPI_TIMEOUT, 1); + if (ret) { + printf("DMA Timeout:0x%x\n", readl(&dma_regs->dmaisr)); + return -ETIMEDOUT; + } + + writel(GQSPI_DMA_DST_I_STS_DONE, &dma_regs->dmaisr); - writel(GQSPI_DMA_DST_I_STS_DONE, &dma_regs->dmaisr); + debug("buf:0x%lx, rxbuf:0x%lx, *buf:0x%x len: 0x%x\n", + (unsigned long)buf, (unsigned long)priv->rx_buf, *buf, + actuallen); - debug("buf:0x%lx, rxbuf:0x%lx, *buf:0x%x len: 0x%x\n", - (unsigned long)buf, (unsigned long)priv->rx_buf, *buf, - actuallen); + if (buf != priv->rx_buf) + memcpy(priv->rx_buf, buf, actuallen); - if (buf != priv->rx_buf) - memcpy(priv->rx_buf, buf, actuallen); + buf = (u32 *)((u8 *)buf + actuallen); + priv->rx_buf = (u8 *)priv->rx_buf + actuallen; + } return 0; } -- 2.7.4