[PATCH 1/4] ARM: rcm-k1879xb1: Add support for K1879XB1 SoC

Russell King - ARM Linux ????? 23.06.2015 19:11:

On Tue, Jun 23, 2015 at 06:50:01PM +0300, Andrew Andrianov wrote:

quoted

+config ARCH_RCM_K1879XB1
+	bool "RC Module K1879XB1YA"
+	depends on MMU
+	select CPU_V6
+        select ARM_AMBA
+	select ARM_VIC

Obviously something's up with the indentation on the ARM_AMBA line...
Also, these select statements should be sorted alphabetically to help
avoid future merge conflicts.

quoted

@@ -1417,6 +1418,7 @@ config DEBUG_UART_PHYS
 	default 0xfffb9800 if DEBUG_OMAP1UART3 || DEBUG_OMAP7XXUART3
 	default 0xfffe8600 if DEBUG_UART_BCM63XX
 	default 0xfffff700 if ARCH_IOP33X
+	default 0x2002b000 if ARCH_RCM_K1879XB1
 	depends on ARCH_EP93XX || \
 	        DEBUG_LL_UART_8250 || DEBUG_LL_UART_PL01X || \
 		DEBUG_LL_UART_EFM32 || \

@@ -1511,6 +1513,7 @@ config DEBUG_UART_VIRT
 	default 0xfefff700 if ARCH_IOP33X
 	default 0xff003000 if DEBUG_U300_UART
 	default 0xffd01000 if DEBUG_HIP01_UART
+	default 0xf802b000 if ARCH_RCM_K1879XB1

Both of these lists have an order - please add your entries in order as
well.

quoted

 	default DEBUG_UART_PHYS if !MMU
 	depends on DEBUG_LL_UART_8250 || DEBUG_LL_UART_PL01X || \
 		DEBUG_UART_8250 || DEBUG_UART_PL01X || DEBUG_MESON_UARTAO || \

diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 985227c..9beb65f 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile

@@ -184,6 +184,7 @@ machine-$(CONFIG_ARCH_OMAP2PLUS)	+= omap2
 machine-$(CONFIG_ARCH_ORION5X)		+= orion5x
 machine-$(CONFIG_ARCH_PICOXCELL)	+= picoxcell
 machine-$(CONFIG_ARCH_PXA)		+= pxa
+machine-$(CONFIG_ARCH_RCM_K1879XB1)	+= rcm-k1879xb1
 machine-$(CONFIG_ARCH_QCOM)		+= qcom

R doesn't come between P and Q, the order of these options is even
documented in the commentry above the list (so here we have more
proof that comments are worthless. :()

Oops, I must've mixed it up during re-bases and it went unnoticed.

quoted

+static struct map_desc k1879_io_desc[] __initdata = {
+	{
+		.virtual	= RCM_K1879_AREA0_VIRT_BASE,
+		.pfn		= __phys_to_pfn(RCM_K1879_AREA0_PHYS_BASE),
+		.length		= RCM_K1879_AREA0_SIZE,
+		.type		= MT_DEVICE,
+	},
+	{
+		.virtual	= RCM_K1879_AREA1_VIRT_BASE,
+		.pfn		= __phys_to_pfn(RCM_K1879_AREA1_PHYS_BASE),
+		.length		= RCM_K1879_AREA1_SIZE,
+		.type		= MT_DEVICE,
+	},
+};

We've moved away from static mapping - is there a reason to keep these?

quoted

+static void __iomem *k1879_mif_base(void)
+{
+	BUG_ON(!g_k1879_mif);
+	return g_k1879_mif;
+}
+
+static void __iomem *k1879_sctl_base(void)
+{
+	return (void __iomem *)RCM_K1879_SCTL_VIRT_BASE;
+}
+
+static void k1879_level_irq_i2c0_fixup(unsigned int irq, struct 
irq_desc *desc)
+{
+	writel(1, k1879_mif_base() + RCM_K1879_MIF_I2C_INT_STAT);
+	handle_level_irq(irq, desc);
+}
+
+static void k1879_level_irq_i2c1_fixup(unsigned int irq, struct 
irq_desc *desc)
+{
+	writel(1 << 0, k1879_sctl_base() + RCM_K1879_SCTL_INT_P_OUT);
+	handle_level_irq(irq, desc);
+}
+
+static void k1879_level_irq_i2c2_fixup(unsigned int irq, struct 
irq_desc *desc)
+{
+	writel(1 << 1, k1879_sctl_base() + RCM_K1879_SCTL_INT_P_OUT);
+	handle_level_irq(irq, desc);
+}
+
+static void k1879_level_irq_i2c3_fixup(unsigned int irq, struct 
irq_desc *desc)
+{
+	writel(1 << 2, k1879_sctl_base() + RCM_K1879_SCTL_INT_P_OUT);
+	handle_level_irq(irq, desc);
+}

I'm not sure this is the best way to deal with this - but I need to 
look
at the irqchip stuff to suggest an alternative.  Maybe you could 
provide
a description of what's going on here first?

As far as I remember that's a workaround. The problem here is that 
Aeroflex
Gaisler i2c has impulse interrupts and that had some hw problems 
connecting
with VIC.
Therefore hardware folks have made it level-triggered, and you have to 
clear
'pending' bit in SCTL register each time the interrupt arrives.

This is very platform-specific, so I don't think hacking i2c driver 
itself would be any
better.

quoted

+void k1879_restart(enum reboot_mode mode, const char *cmd)

static?

quoted

+{
+	/* The recommended way to do a soft-reboot on this platform
+	   is write directly to watchdog registers and cause an immediate
+	   system reboot
+	*/
+	void __iomem *regs;
+
+	pr_info("k1879: Requested system restart\n");

I assume this is debugging - do you need to print this?

quoted

+	regs = ioremap_nocache(0x20025000, 0xfff);

Please use ioremap() instead.  Both of these calls may sleep, and so
should not be used in this path (which can be called from atomic
contexts.)  Hence, this needs to happen elsewhere (in your 
.init_machine
method.)

Thanks for the quick response, I'll fix all the things you've noted and 
resend
the patches tomorrow.

-- 
Regards,
Andrew
RC Module :: http://module.ru