Re: [PATCH 03/22] ARM: omap1: move omap15xx local bus handling to usb.c

From: Christoph Hellwig
Date: Sat Aug 10 2019 - 06:28:34 EST


Thanks for doing this! The odd platforms have always been very
confusing.

> diff --git a/arch/arm/mach-omap1/include/mach/omap1510.h b/arch/arm/mach-omap1/include/mach/omap1510.h
> index 3d235244bf5c..7af9c0c7c5ab 100644
> --- a/arch/arm/mach-omap1/include/mach/omap1510.h
> +++ b/arch/arm/mach-omap1/include/mach/omap1510.h
> @@ -159,4 +159,3 @@
> #define OMAP1510_INT_FPGA23 (OMAP_FPGA_IRQ_BASE + 23)
>
> #endif /* __ASM_ARCH_OMAP15XX_H */
> -

Spurious whitespace change?

> diff --git a/arch/arm/mach-omap1/usb.c b/arch/arm/mach-omap1/usb.c
> index d8e9bbda8f7b..740c876ae46b 100644
> --- a/arch/arm/mach-omap1/usb.c
> +++ b/arch/arm/mach-omap1/usb.c
> @@ -10,6 +10,7 @@
> #include <linux/init.h>
> #include <linux/platform_device.h>
> #include <linux/io.h>
> +#include <linux/delay.h>
>
> #include <asm/irq.h>
>
> @@ -127,6 +128,7 @@ omap_otg_init(struct omap_usb_config *config)
>
> syscon &= ~HST_IDLE_EN;
> ohci_device->dev.platform_data = config;
> +
> status = platform_device_register(ohci_device);

Same here.

> +#define OMAP1510_LB_OFFSET UL(0x30000000)
> +#define OMAP1510_LB_DMA_PFN_OFFSET ((OMAP1510_LB_OFFSET - PAGE_OFFSET) >> PAGE_SHIFT)

Overly long line.

> +/*
> + * OMAP-1510 specific Local Bus clock on/off
> + */
> +static int omap_1510_local_bus_power(int on)
> +{
> + if (on) {
> + omap_writel((1 << 1) | (1 << 0), OMAP1510_LB_MMU_CTL);
> + udelay(200);
> + } else {
> + omap_writel(0, OMAP1510_LB_MMU_CTL);
> + }
> +
> + return 0;
> +}

The caller never checks the const return value, and on is always true as
well. In fact it seems like omap_1510_local_bus_power and
omap_1510_local_bus_init could probably just be merged into the caller.

> +
> +/*
> + * OMAP-1510 specific Local Bus initialization
> + * NOTE: This assumes 32MB memory size in OMAP1510LB_MEMSIZE.
> + * See also arch/mach-omap/memory.h for __virt_to_dma() and
> + * __dma_to_virt() which need to match with the physical
> + * Local Bus address below.

I think that NOTE is out of date, as __virt_to_dma and __dma_to_virt
don't exist anymore.

> +static int omap_1510_local_bus_init(void)
> +{
> + unsigned int tlb;
> + unsigned long lbaddr, physaddr;
> +
> + omap_writel((omap_readl(OMAP1510_LB_CLOCK_DIV) & 0xfffffff8) | 0x4,
> + OMAP1510_LB_CLOCK_DIV);
> +
> + /* Configure the Local Bus MMU table */
> + for (tlb = 0; tlb < OMAP1510_LB_MEMSIZE; tlb++) {
> + lbaddr = tlb * 0x00100000 + OMAP1510_LB_OFFSET;
> + physaddr = tlb * 0x00100000 + PHYS_OFFSET;
> + omap_writel((lbaddr & 0x0fffffff) >> 22, OMAP1510_LB_MMU_CAM_H);
> + omap_writel(((lbaddr & 0x003ffc00) >> 6) | 0xc,
> + OMAP1510_LB_MMU_CAM_L);
> + omap_writel(physaddr >> 16, OMAP1510_LB_MMU_RAM_H);
> + omap_writel((physaddr & 0x0000fc00) | 0x300, OMAP1510_LB_MMU_RAM_L);

Another > 80 chars line.

> + omap_writel(tlb << 4, OMAP1510_LB_MMU_LCK);
> + omap_writel(0x1, OMAP1510_LB_MMU_LD_TLB);
> + }
> +
> + /* Enable the walking table */
> + omap_writel(omap_readl(OMAP1510_LB_MMU_CTL) | (1 << 3), OMAP1510_LB_MMU_CTL);

One more.

> + udelay(200);
> +
> + return 0;

The return value is ignored.