RE: [PATCH] crypt: bfin_crc: Remove useless SSYNC instruction and cache flush to DMA coherent memory

-----Original Message-----
From: Sonic Zhang [mailto:sonic.adi@gmail.com]
Sent: Wednesday, February 26, 2014 10:39 AM
To: Herbert Xu
Cc: linux-crypto@vger.kernel.org; adi-buildroot-devel@lists.sourceforge.net; Zhang,
Sonic
Subject: [PATCH] crypt: bfin_crc: Remove useless SSYNC instruction and cache
flush to DMA coherent memory

From: Sonic Zhang <redacted>

1) SSYNC instruction is blackfin specific and takes no effect in this driver.
2) DMA descriptor and SG middle buffer are in DMA coherent memory. No need to
flush.
3) Turn kzalloc, ioremap and request_irq into managed device APIs respectively.

Signed-off-by: Sonic Zhang <redacted>
---
drivers/crypto/bfin_crc.c | 45 +++++++++++----------------------------------
1 file changed, 11 insertions(+), 34 deletions(-)

diff --git a/drivers/crypto/bfin_crc.c b/drivers/crypto/bfin_crc.c index d797f31..c9ff298

100644

--- a/drivers/crypto/bfin_crc.c
+++ b/drivers/crypto/bfin_crc.c

@@ -139,7 +139,6 @@ static int bfin_crypto_crc_init_hw(struct bfin_crypto_crc *crc,

u32 key)
      /* setup CRC interrupts */
      crc->regs->status = CMPERRI | DCNTEXPI;
      crc->regs->intrenset = CMPERRI | DCNTEXPI;
-      SSYNC();

      return 0;
}

@@ -285,17 +284,12 @@ static void bfin_crypto_crc_config_dma(struct

bfin_crypto_crc *crc)
      if (i == 0)
              return;

-      flush_dcache_range((unsigned int)crc->sg_cpu,
-                      (unsigned int)crc->sg_cpu +
-                      i * sizeof(struct dma_desc_array));
-
      /* Set the last descriptor to stop mode */
      crc->sg_cpu[i - 1].cfg &= ~(DMAFLOW | NDSIZE);
      crc->sg_cpu[i - 1].cfg |= DI_EN;
      set_dma_curr_desc_addr(crc->dma_ch, (unsigned long *)crc->sg_dma);
      set_dma_x_count(crc->dma_ch, 0);
      set_dma_x_modify(crc->dma_ch, 0);
-      SSYNC();
      set_dma_config(crc->dma_ch, dma_config);  }

@@ -415,7 +409,6 @@ finish_update:

      /* finally kick off CRC operation */
      crc->regs->control |= BLKEN;
-      SSYNC();

      return -EINPROGRESS;

}

@@ -539,7 +532,6 @@ static irqreturn_t bfin_crypto_crc_handler(int irq, void

*dev_id)

      if (crc->regs->status & DCNTEXP) {
              crc->regs->status = DCNTEXP;
-              SSYNC();

              /* prepare results */
              put_unaligned_le32(crc->regs->result, crc->req->result); @@ -594,7
+586,7 @@ static int bfin_crypto_crc_probe(struct platform_device *pdev)
      unsigned int timeout = 100000;
      int ret;

-      crc = kzalloc(sizeof(*crc), GFP_KERNEL);
+      crc = devm_kzalloc(dev, sizeof(*crc), GFP_KERNEL);
      if (!crc) {
              dev_err(&pdev->dev, "fail to malloc bfin_crypto_crc\n");
              return -ENOMEM;

@@ -610,42 +602,39 @@ static int bfin_crypto_crc_probe(struct platform_device

*pdev)
      res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
      if (res == NULL) {
              dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
-              ret = -ENOENT;
-              goto out_error_free_mem;
+              return -ENOENT;
      }

-      crc->regs = ioremap(res->start, resource_size(res));
-      if (!crc->regs) {
+      crc->regs = devm_ioremap_resource(dev, res);
+      if (IS_ERR((void *)crc->regs)) {
              dev_err(&pdev->dev, "Cannot map CRC IO\n");
-              ret = -ENXIO;
-              goto out_error_free_mem;
+              return PTR_ERR((void *)crc->regs);
      }

      crc->irq = platform_get_irq(pdev, 0);
      if (crc->irq < 0) {
              dev_err(&pdev->dev, "No CRC DCNTEXP IRQ specified\n");
-              ret = -ENOENT;
-              goto out_error_unmap;
+              return -ENOENT;
      }

-      ret = request_irq(crc->irq, bfin_crypto_crc_handler, IRQF_SHARED,
dev_name(dev), crc);
+      ret = devm_request_irq(dev, crc->irq, bfin_crypto_crc_handler,
+                      IRQF_SHARED, dev_name(dev), crc);
      if (ret) {
              dev_err(&pdev->dev, "Unable to request blackfin crc irq\n");
-              goto out_error_unmap;
+              return ret;
      }

      res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
      if (res == NULL) {
              dev_err(&pdev->dev, "No CRC DMA channel specified\n");
-              ret = -ENOENT;
-              goto out_error_irq;
+              return -ENOENT;
      }
      crc->dma_ch = res->start;

      ret = request_dma(crc->dma_ch, dev_name(dev));
      if (ret) {
              dev_err(&pdev->dev, "Unable to attach Blackfin CRC DMA
channel\n");
-              goto out_error_irq;
+              return ret;
      }

      crc->sg_cpu = dma_alloc_coherent(&pdev->dev, PAGE_SIZE, &crc->sg_dma,
GFP_KERNEL); @@ -660,9 +649,7 @@ static int bfin_crypto_crc_probe(struct
platform_device *pdev)
      crc->sg_mid_buf = (u8 *)(crc->sg_cpu + ((CRC_MAX_DMA_DESC + 1) <<
1));

      crc->regs->control = 0;
-      SSYNC();
      crc->regs->poly = crc->poly = (u32)pdev->dev.platform_data;
-      SSYNC();

      while (!(crc->regs->status & LUTDONE) && (--timeout) > 0)
              cpu_relax();

@@ -693,12 +680,6 @@ out_error_dma:
      if (crc->sg_cpu)
              dma_free_coherent(&pdev->dev, PAGE_SIZE, crc->sg_cpu, crc-

quoted

sg_dma);

      free_dma(crc->dma_ch);
-out_error_irq:
-      free_irq(crc->irq, crc);
-out_error_unmap:
-      iounmap((void *)crc->regs);
-out_error_free_mem:
-      kfree(crc);

      return ret;
}

@@ -721,10 +702,6 @@ static int bfin_crypto_crc_remove(struct platform_device

*pdev)
      crypto_unregister_ahash(&algs);
      tasklet_kill(&crc->done_task);
      free_dma(crc->dma_ch);
-      if (crc->irq > 0)
-              free_irq(crc->irq, crc);
-      iounmap((void *)crc->regs);
-      kfree(crc);

      return 0;
}
--
1.8.2.3