From: Stephen Warren <redacted>
Subject: Re: [PATCHv3 1/4] ARM: tegra: Add Tegra AHB driver
Date: Thu, 3 May 2012 19:41:35 +0200
Message-ID: [ref]

On 05/03/2012 10:05 AM, Hiroshi DOYU wrote:

quoted

Tegra AHB Bus conforms to the AMBA Specification (Rev 2.0) Advanced
High-performance Bus (AHB) architecture.

The AHB Arbiter controls AHB bus master arbitration. This effectively
forms a second level of arbitration for access to the memory
controller through the AHB Slave Memory device. The AHB pre-fetch
logic can be configured to enhance performance for devices doing
sequential access. Each AHB master is assigned to either the high or
low priority bin. Both Tegra20/30 have this AHB bus.

Some of configuration param could be passed from DT too.

quoted

diff --git a/drivers/amba/tegra-ahb.c b/drivers/amba/tegra-ahb.c
+static u32 tegra_ahb_gizmo[] = {

const?

Yes.

quoted

+static int __init tegra_ahb_module_init(void)
+{
+	return platform_driver_register(&tegra_ahb_driver);
+}
+postcore_initcall(tegra_ahb_module_init);

Can this be a module_init() instead of postcore_initcall()?

Since this driver configures prefetch size from AHB client devices,
it's better to make this driver available before other AHB client
drivers get ready. So "postcore_initcall()" seems to make sense if
there's no other better initcall.

quoted

+
+static void __exit tegra_ahb_module_exit(void)
+{
+	platform_driver_unregister(&tegra_ahb_driver);
+}
+module_exit(tegra_ahb_module_exit);

If so, all of the previous two quoted chunks can be replaced with just:

module_platform_driver(tegra_ahb_module_init);