Date:   Thu, 13 Oct 2022 14:48:29 +0800
From:   Rahul Tanwar <rtanwar@...linear.com>
To:     <sboyd@...nel.org>, <mturquette@...libre.com>,
        <linux-clk@...r.kernel.org>, <yzhu@...linear.com>
CC:     <linux-kernel@...r.kernel.org>, <linux-lgm-soc@...linear.com>,
        "Rahul Tanwar" <rtanwar@...linear.com>
Subject: [PATCH v4 0/4] Modify MxL's CGU clk driver to make it secure boot compatible

MxL's CGU driver was found to be lacking below required features. Add these
required lacking features:

1. Since it is a core driver, it has to conform to secure boot & secure
   access architecture. In order for the register accesses to be secure
   access compliant, it needs regmap support as per our security architecture.
   Hence, replace direct read/writel with regmap based IO. Also remove
   redundant spinlocks from the driver as they are no longer necessary
   because regmap uses its own lock.

2. In MxL's LGM SoC, gate clocks can be controlled either from CGU clk driver
   i.e. this driver or directly from power management driver/daemon. It is
   dependent on the power policy/profile requirements of the end product.

   To support such use cases, provide option to override gate clks enable/disable
   by adding a flag GATE_CLK_HW which controls if these gate clks are controlled
   by HW i.e. this driver or overridden in order to allow it to be controlled
   by power profiles instead.

3. Fix a bug related to missing flags in one 'dcl' clk entry.

This patch series is based on below git tree (linux-v6.0-rc1):
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git

v4:
- Address review concern (Stephen Boyd)
- Change the design of how GATE_CLKs are overridden.
  Make the clk provider return NULL when that clk needs
  to be overridden.

v3:
- Address review concern (Stephen Boyd)
- Change the method of fixing invalid width for reg read/write.

v2:
- Add option to override gate clks
- Fix a clk entry by adding relevant flags

v1:
- Initial version

Rahul Tanwar (4):
  clk: mxl: Switch from direct readl/writel based IO to regmap based IO
  clk: mxl: Remove redundant spinlocks
  clk: mxl: Add option to override gate clks
  clk: mxl: Fix a clk entry by adding relevant flags

 drivers/clk/x86/Kconfig       |   5 +-
 drivers/clk/x86/clk-cgu-pll.c |  23 ++------
 drivers/clk/x86/clk-cgu.c     | 105 ++++++++++------------------------
 drivers/clk/x86/clk-cgu.h     |  46 +++++++--------
 drivers/clk/x86/clk-lgm.c     |  18 +++---
 5 files changed, 72 insertions(+), 125 deletions(-)

-- 
2.17.1

Powered by blists - more mailing lists