On Thu, 29 Apr 2010 21:05:26 -0500
Timur Tabi [off-list ref] wrote:

On Thu, Apr 29, 2010 at 6:49 PM, Anatolij Gustschin [off-list ref] wrote:

quoted

+void __init mpc5121_ads_init_early(void)
+{
+       mpc512x_init_diu();
+}
+
 define_machine(mpc5121_ads) {
       .name                   = "MPC5121 ADS",
       .probe                  = mpc5121_ads_probe,
       .setup_arch             = mpc5121_ads_setup_arch,
       .init                   = mpc512x_init,
+       .init_early             = mpc5121_ads_init_early,

How about just doing this?

.init_early             = mpc512x_init_diu,

I thought it should be prepared for adding other code here.
mpc5121_ads_init_early() is generic and could contain other
things as well. I would vote for current version.

quoted

+void __init mpc512x_generic_init_early(void)
+{
+       mpc512x_init_diu();
+}
+
+void __init mpc512x_generic_setup_arch(void)
+{
+       mpc512x_setup_diu();
+}
+
 define_machine(mpc5121_generic) {
       .name                   = "MPC5121 generic",
       .probe                  = mpc5121_generic_probe,
       .init                   = mpc512x_init,
+       .init_early             = mpc512x_generic_init_early,
+       .setup_arch             = mpc512x_generic_setup_arch,

And a similar change here.

Same here.

...

quoted

diff --git a/arch/powerpc/platforms/512x/mpc512x_shared.c b/arch/powerpc/platforms/512x/mpc512x_shared.c
index b7f518a..8e297fa 100644
--- a/arch/powerpc/platforms/512x/mpc512x_shared.c
+++ b/arch/powerpc/platforms/512x/mpc512x_shared.c

@@ -16,7 +16,11 @@

 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/of_platform.h>
+#include <linux/fsl-diu-fb.h>
+#include <linux/bootmem.h>
+#include <sysdev/fsl_soc.h>

+#include <asm/cacheflush.h>
 #include <asm/machdep.h>
 #include <asm/ipic.h>
 #include <asm/prom.h>

@@ -53,6 +57,286 @@ void mpc512x_restart(char *cmd)

               ;
 }

+struct fsl_diu_shared_fb {
+       char            gamma[0x300];   /* 32-bit aligned! */

char or u8?

Will use u8.

quoted

+       struct diu_ad   ad0;            /* 32-bit aligned! */
+       phys_addr_t     fb_phys;
+       size_t          fb_len;
+       bool            in_use;
+};

Where did "bool" come from?  Use "int" instead.

It is common practise to use "bool" type, grep in drivers dir.

quoted

+unsigned int mpc512x_get_pixel_format(unsigned int bits_per_pixel,
+                                     int monitor_port)
+{
+       unsigned int pix_fmt;
+
+       switch (bits_per_pixel) {
+       case 32:
+               pix_fmt = 0x88883316;
+               break;
+       case 24:
+               pix_fmt = 0x88082219;
+               break;
+       case 16:
+               pix_fmt = 0x65053118;
+               break;
+       default:
+               pix_fmt = 0x00000400;
+       }
+       return pix_fmt;
+}

This is simpler:

       switch (bits_per_pixel) {
       case 32:
               return 0x88883316;
       case 24:
               return 0x88082219;
       case 16:
               return = 0x65053118;
      }

      return 0x00000400;
}

Will simplify as suggested, thanks!

quoted

+       ccm = of_iomap(np, 0);
+       if (!ccm) {
+               pr_err("Can't map clock control module reg.\n");
+               of_node_put(np);
+               return;
+       }
+       of_node_put(np);

This is simpler:

       ccm = of_iomap(np, 0);
       of_node_put(np);
       if (!ccm) {
               pr_err("Can't map clock control module reg.\n");
               return;
       }

OK, will fix, thanks.

quoted

+       np = of_find_node_by_type(NULL, "cpu");
+       if (np) {
+               unsigned int size;
+               const unsigned int *prop > > +                       of_get_property(np, "bus-frequency", &size);

Since you don't use 'size', you can skip it:

              const unsigned int *prop >                       of_get_property(np, "bus-frequency", NULL);

quoted

+       } else {
+               pr_err("Can't find \"cpu\" node.\n");

'cpu' is simpler than \"cpu\"

Will simplify, too.

quoted

+       /* Calculate the pixel clock with the smallest error */
+       /* calculate the following in steps to avoid overflow */
+       pr_debug("DIU pixclock in ps - %d\n", pixclock);
+       temp = (1000000000 / pixclock) * 1000;

I'm pretty sure the compiler will optimize this to:

    temp = (1000000000000UL / pixclock);

so you may as well do it that way.

??
1000000000000 is _not_ UL, but UUL.

quoted

+       pixclock = temp;
+       pr_debug("DIU pixclock freq - %u\n", pixclock);
+
+       temp = (temp * 5) / 100; /* pixclock * 0.05 */

The compiler will optimize this to:

    temp /= 20;

Can do it, too. Thanks.

quoted

+       pr_debug("deviation = %d\n", temp);
+       minpixclock = pixclock - temp;
+       maxpixclock = pixclock + temp;
+       pr_debug("DIU minpixclock - %lu\n", minpixclock);
+       pr_debug("DIU maxpixclock - %lu\n", maxpixclock);
+       pixval = speed_ccb/pixclock;
+       pr_debug("DIU pixval = %lu\n", pixval);
+
+       err = 100000000;

Why do you assign err to this arbitrary value?

Dunno. It is Freescale's code and I do not have time to check
and understand each bit of it and to explain it.

quoted

+       bestval = pixval;
+       pr_debug("DIU bestval = %lu\n", bestval);
+
+       bestfreq = 0;
+       for (i = -1; i <= 1; i++) {
+               temp = speed_ccb / (pixval+i);
+               pr_debug("DIU test pixval i=%d, pixval=%lu, temp freq. = %u\n",
+                       i, pixval, temp);
+               if ((temp < minpixclock) || (temp > maxpixclock))
+                       pr_debug("DIU exceeds monitor range (%lu to %lu)\n",
+                               minpixclock, maxpixclock);
+               else if (abs(temp - pixclock) < err) {
+                       pr_debug("Entered the else if block %d\n", i);
+                       err = abs(temp - pixclock);
+                       bestval = pixval + i;
+                       bestfreq = temp;
+               }
+       }
+
+       pr_debug("DIU chose = %lx\n", bestval);
+       pr_debug("DIU error = %ld\n NomPixClk ", err);
+       pr_debug("DIU: Best Freq = %lx\n", bestfreq);
+       /* Modify DIU_DIV in CCM SCFR1 */
+       temp = in_be32(ccm + CCM_SCFR1);

Don't use offsets like + CCM_SCFR1.  Create a structure and use that instead.

Done in next patch version.

quoted

+       pr_debug("DIU: Current value of SCFR1: 0x%08x\n", temp);
+       temp &= ~DIU_DIV_MASK;
+       temp |= (bestval & DIU_DIV_MASK);
+       out_be32(ccm + CCM_SCFR1, temp);
+       pr_debug("DIU: Modified value of SCFR1: 0x%08x\n", temp);
+       iounmap(ccm);
+}
+
+ssize_t mpc512x_show_monitor_port(int monitor_port, char *buf)
+{
+       return snprintf(buf, PAGE_SIZE, "0 - 5121 LCD\n");

There's no point in using snprintf since you're printing a string
literal.  You can use sprintf.

Will do, thanks.

quoted

+}
+
+int mpc512x_set_sysfs_monitor_port(int val)
+{
+       return 0;
+}
+
+static struct fsl_diu_shared_fb __attribute__ ((__aligned__(8))) diu_shared_fb;
+
+#if defined(CONFIG_FB_FSL_DIU) || \
+    defined(CONFIG_FB_FSL_DIU_MODULE)
+static inline void mpc512x_free_bootmem(struct page *page)
+{
+       __ClearPageReserved(page);
+       BUG_ON(PageTail(page));
+       BUG_ON(atomic_read(&page->_count) > 1);
+       atomic_set(&page->_count, 1);
+       __free_page(page);
+       totalram_pages++;
+}
+
+void mpc512x_release_bootmem(void)
+{
+       unsigned long addr = diu_shared_fb.fb_phys & PAGE_MASK;
+       unsigned long size = diu_shared_fb.fb_len;
+       unsigned long start, end;
+
+       if (diu_shared_fb.in_use) {
+               start = PFN_UP(addr);
+               end = PFN_DOWN(addr + size);
+
+               for (; start < end; start++)
+                       mpc512x_free_bootmem(pfn_to_page(start));
+
+               diu_shared_fb.in_use = false;
+       }
+       diu_ops.release_bootmem = NULL;
+}
+#endif

Do you really need to use reserve_bootmem?  Have you tried kmalloc or
alloc_pages_exact()?

Yes. No, it is too early to use them here.

quoted

+
+/*
+ * Check if DIU was pre-initialized. If so, perform steps
+ * needed to continue displaying through the whole boot process.
+ * Move area descriptor and gamma table elsewhere, they are
+ * destroyed by bootmem allocator otherwise. The frame buffer
+ * address range will be reserved in setup_arch() after bootmem
+ * allocator is up.
+ */
+void __init mpc512x_init_diu(void)
+{
+       struct device_node *np;
+       void __iomem *diu_reg;
+       phys_addr_t desc;
+       void __iomem *vaddr;
+       unsigned long mode, pix_fmt, res, bpp;
+       unsigned long dst;
+
+       np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-diu");
+       if (!np) {
+               pr_err("No DIU node\n");
+               return;
+       }

Shouldn't you be probing as an OF driver instead of manually searching
for the DIU node?

No, not here.

quoted

+
+       diu_reg = of_iomap(np, 0);
+       of_node_put(np);
+       if (!diu_reg) {
+               pr_err("Can't map DIU\n");
+               return;
+       }
+
+       mode = in_be32(diu_reg + 0x1c);
+       if (mode != 1) {

How can in_be32() return a -1?

It is a 1, not -1. I will use appropriate macro here and also
change to use a struct instead of adding offset to register base.

Thanks for your review and comments!
Anatolij