[PATCH v1 2/2] x86/platform/intel-mid: Keep SRAM powered on at boot

From: Andy Shevchenko
Date: Thu Sep 08 2016 - 06:33:16 EST


On Penwell SRAM has to be powered on, otherwise it prevents booting.

Fixes: ca22312dc840 ("x86/platform/intel-mid: Extend PWRMU to support Penwell")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
arch/x86/platform/intel-mid/pwr.c | 45 +++++++++++++++++++++++++++++++--------
1 file changed, 36 insertions(+), 9 deletions(-)

diff --git a/arch/x86/platform/intel-mid/pwr.c b/arch/x86/platform/intel-mid/pwr.c
index 146ed54..5d3b45a 100644
--- a/arch/x86/platform/intel-mid/pwr.c
+++ b/arch/x86/platform/intel-mid/pwr.c
@@ -380,7 +380,7 @@ static int mid_pwr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
return 0;
}

-static int mid_set_initial_state(struct mid_pwr *pwr)
+static int mid_set_initial_state(struct mid_pwr *pwr, const u32 *states)
{
unsigned int i, j;
int ret;
@@ -405,10 +405,10 @@ static int mid_set_initial_state(struct mid_pwr *pwr)
* NOTE: The actual device mapping is provided by a platform at run
* time using vendor capability of PCI configuration space.
*/
- mid_pwr_set_state(pwr, 0, 0xffffffff);
- mid_pwr_set_state(pwr, 1, 0xffffffff);
- mid_pwr_set_state(pwr, 2, 0xffffffff);
- mid_pwr_set_state(pwr, 3, 0xffffffff);
+ mid_pwr_set_state(pwr, 0, states[0]);
+ mid_pwr_set_state(pwr, 1, states[1]);
+ mid_pwr_set_state(pwr, 2, states[2]);
+ mid_pwr_set_state(pwr, 3, states[3]);

/* Send command to SCU */
ret = mid_pwr_wait_for_cmd(pwr, CMD_SET_CFG);
@@ -423,14 +423,41 @@ static int mid_set_initial_state(struct mid_pwr *pwr)
return 0;
}

-static const struct mid_pwr_device_info mid_info = {
- .set_initial_state = mid_set_initial_state,
+static int pnw_set_initial_state(struct mid_pwr *pwr)
+{
+ /* On Penwell SRAM must stay powered on */
+ const u32 states[] = {
+ 0xf00fffff, /* PM_SSC(0) */
+ 0xffffffff, /* PM_SSC(1) */
+ 0xffffffff, /* PM_SSC(2) */
+ 0xffffffff, /* PM_SSC(3) */
+ };
+ return mid_set_initial_state(pwr, states);
+}
+
+static int tng_set_initial_state(struct mid_pwr *pwr)
+{
+ const u32 states[] = {
+ 0xffffffff, /* PM_SSC(0) */
+ 0xffffffff, /* PM_SSC(1) */
+ 0xffffffff, /* PM_SSC(2) */
+ 0xffffffff, /* PM_SSC(3) */
+ };
+ return mid_set_initial_state(pwr, states);
+}
+
+static const struct mid_pwr_device_info pnw_info = {
+ .set_initial_state = pnw_set_initial_state,
+};
+
+static const struct mid_pwr_device_info tng_info = {
+ .set_initial_state = tng_set_initial_state,
};

/* This table should be in sync with the one in drivers/pci/pci-mid.c */
static const struct pci_device_id mid_pwr_pci_ids[] = {
- { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PENWELL), (kernel_ulong_t)&mid_info },
- { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_TANGIER), (kernel_ulong_t)&mid_info },
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PENWELL), (kernel_ulong_t)&pnw_info },
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_TANGIER), (kernel_ulong_t)&tng_info },
{}
};

--
2.9.3